Dizziness
Clinical Snapshot
Dizziness is one of the most common symptoms encountered in primary care and among the most common reasons for an emergency department visit, yet it remains genuinely challenging to work up efficiently — the word is nonspecific, and different patients (and the same patient on different days) use it to describe genuinely different sensations. A Canadian chart-audit study at a Toronto family practice clinic notes that dizziness affects over 30% of people aged 65 and older, and found that documentation of the basic quality indicators needed to work it up properly — the patient's own description of the sensation, a current medication list, orthostatic blood pressure measurement, a falls history, and screening for depression — was frequently incomplete in routine practice.[1] That documented practice gap is exactly where a pharmacist's structured medication review adds the most value.
This chapter is deliberately scoped to the general, pharmacist-relevant medication-induced and multifactorial dizziness workup — the classification framework, the mechanism-based medication differential, the structured review process, and falls-prevention counselling that apply across causes. It does not cover the specific mechanism and treatment of benign paroxysmal positional vertigo (BPPV), which has its own dedicated chapter covering canalithiasis, the Dix-Hallpike test, and the Epley/Semont repositioning maneuvers — cross-reference that chapter whenever the history and bedside testing point specifically to BPPV.
Four categories, and an important caveat about them
Since 1972, dizziness has traditionally been divided into 4 categories based on the patient's own description of the sensation — a framework still worth knowing as a starting vocabulary for organizing the differential:[2]
| Category | Patient description | Typical underlying mechanism |
|---|---|---|
| Vertigo | A true illusion of movement — the room spinning, or the sensation of spinning oneself | Vestibular — peripheral (e.g., BPPV, vestibular neuritis, Ménière's disease) or, less often, central |
| Presyncope | Light-headedness, feeling faint, "the room going grey," typically worse on standing | Cardiovascular or orthostatic — reduced cerebral perfusion |
| Disequilibrium | Unsteadiness or imbalance specifically on the feet, without a spinning or faint sensation while seated | Neurologic, musculoskeletal, visual, or multisensory — including sedating medications impairing balance |
| Nonspecific / psychogenic dizziness | A vague, hard-to-characterize sensation not clearly fitting the other 3 categories | Anxiety, hyperventilation, persistent postural-perceptual dizziness, or an evolving pattern that has not yet declared itself |
The framework's own modern restatement is honest about its limits: the distinction patients draw between these categories is often unreliable in practice, since many cannot cleanly separate "spinning" from "light-headed," and the same patient may describe genuinely different sensations differently on different visits.[3] A newer, complementary approach — TiTrATE (Timing, Triggers, a Targeted Exam) — classifies dizziness instead by its temporal pattern (episodic vs. continuous) and its triggers (positional, orthostatic, spontaneous), mapping more directly onto an actionable diagnostic pathway and increasingly preferred for acute presentations.[4] In practice the two frameworks work well together: symptom quality is a reasonable starting point for organizing the differential, and timing/triggers refine it once a category is suspected — both are used throughout this chapter.
Recognize the Condition
Presentation by category
What each category actually looks like
Vertigo
A genuine illusion of rotational movement, often with nausea and nystagmus. When it is brief and specifically triggered by a head-position change, consider BPPV and move to that chapter's Dix-Hallpike-driven workup. When it is continuous and lasts hours to days, or is accompanied by hearing loss/tinnitus (Ménière's disease) or a recent viral illness (vestibular neuritis/labyrinthitis), a different peripheral cause is more likely. Continuous vertigo with any neurologic sign is a red flag — see Red Flags & Refer.
Presyncope
Light-headedness or a feeling of impending faint, classically worse on standing or after a meal, and relieved by sitting or lying down. This is the pattern most directly relevant to medication review, since orthostatic hypotension from antihypertensives is one of the single most common identifiable causes in an older adult.[5]
Disequilibrium
Unsteadiness specifically on the feet — the patient feels fine sitting or lying down, but unsteady when walking — without true spinning or faintness. Peripheral neuropathy, visual impairment, cervical spondylosis, Parkinsonism, and sedating medications that blunt proprioceptive and vestibular integration all present this way.
Nonspecific / psychogenic dizziness
A vague sensation the patient struggles to characterize precisely. Anxiety and hyperventilation are genuine causes, but this category should be a diagnosis of exclusion after red flags and a medication contribution have been considered, not a first assumption.
The medication-induced dizziness differential, organized by mechanism
This is the differential most directly actionable by a pharmacist. 4 mechanisms account for the great majority of medication-induced dizziness, and a single patient — particularly an older adult on multiple drugs — can have more than 1 operating at once.
Mechanism 1 — Orthostatic hypotension
A drop in blood pressure on standing, presenting as presyncope specifically on postural change. Antihypertensives and diuretics — hydrochlorothiazide, chlorthalidone, indapamide, furosemide, ramipril, losartan, nifedipine — are the largest class. Alpha-blockers — doxazosin, terazosin, prazosin, and tamsulosin (prescribed for BPH, often in men already on an antihypertensive) — carry a particularly high first-dose and dose-increase risk. Central alpha-2 agonists — clonidine, methyldopa — combine OH with sedation. Tricyclic antidepressants — amitriptyline, nortriptyline — cause OH through alpha-1 blockade on top of their own anticholinergic and sedative effects, a genuine triple risk in 1 drug.
Mechanism 2 — Vestibulotoxicity
Direct toxic injury to the cochlea and/or vestibular apparatus, sometimes irreversible if not caught early. Aminoglycosides — gentamicin, tobramycin, streptomycin — are the classic cause, risk rising with cumulative dose, duration beyond about a week, and renal impairment. vancomycin is not itself an aminoglycoside but carries real synergistic ototoxicity risk when combined with one. Loop diuretics — furosemide — are ototoxic mainly at high IV doses or rapid infusion, and add to aminoglycoside risk when combined. High-dose salicylates — sustained high-dose acetylsalicylic acid (not typical low-dose cardioprotective use) — cause a reversible pattern with tinnitus as the classic early warning sign. quinine, still sometimes used off-label for nocturnal leg cramps, causes the same reversible cinchonism-like picture.
Mechanism 3 — Sedation and CNS depression
Impaired alertness, balance integration, and reaction time, presenting as disequilibrium or nonspecific dizziness. Benzodiazepines — diazepam, lorazepam, clonazepam, oxazepam — and the non-benzodiazepine hypnotic zopiclone are flagged equally by both the AGS Beers Criteria and Choosing Wisely Canada's geriatrics recommendation.[6][7] Opioids — morphine, oxycodone, hydromorphone, codeine — cause dizziness through both sedation and opioid-related orthostatic hypotension, most pronounced at initiation or dose increase. Anticholinergics and first-generation antihistamines — diphenhydramine, hydroxyzine, dimenhydrinate, oxybutynin — combine sedation with anticholinergic confusion; the first 3 are also widely available OTC, so ask about them explicitly since patients rarely volunteer OTC use. Antiepileptics — gabapentin, pregabalin, phenytoin, carbamazepine — cause dose-related dizziness that, for phenytoin specifically, tracks closely with serum level and can signal a supratherapeutic level.
Mechanism 4 — Hypoglycemia
Autonomic and neuroglycopenic symptoms presenting as a presyncope-like dizziness, sometimes with sweating and confusion. insulin and the sulfonylureas — glyburide, gliclazide, glimepiride — are the relevant classes; hypoglycemia unawareness is more common in older adults and in those with autonomic neuropathy, so the classic warning symptoms may be blunted or absent.
Polypharmacy — the cumulative risk that outweighs any single drug
Even without 1 obvious culprit, the sheer number of medications independently raises dizziness and fall risk. A Canadian systematic review of medications and polypharmacy in community-dwelling recurrent fallers found a consistent association between the number of medications taken and recurrent falls across the reviewed literature — this is a genuine, additive risk, not simply a marker for being generally unwell.[8] This is exactly why a structured screen against the AGS Beers Criteria and STOPP/START version 3 (see Assessment & Diagnosis) is worth applying to the whole medication list, not just to the drug the patient suspects.[6][9]
Risk Factors
- Age 65 years or older — dizziness affects over 30% of people in this group.
- Polypharmacy — taking 5 or more regular medications independently and cumulatively raises dizziness and fall risk, even without 1 clearly identifiable culprit drug.
- A new medication or a recent dose change/increase, particularly for an antihypertensive, a diuretic, a sedating drug, or a hypoglycemic agent.
- Renal or hepatic impairment — reduces clearance of many of the relevant drug classes (gabapentin, opioids, benzodiazepine metabolites, aminoglycosides), raising effective exposure without a dose change.
- Frailty, low body weight, or recent acute illness/dehydration — reduces the physiologic reserve to compensate for a medication effect.
- Autonomic neuropathy (longstanding diabetes) or Parkinson disease — both blunt the normal compensatory response to orthostatic stress, compounding a drug's own OH risk.
- A prior fall or near-fall.
- Sensory impairment — vision, hearing, or peripheral proprioception — reduces the redundant sensory input the balance system normally relies on.
- Cognitive impairment — both a risk factor in its own right and a reason symptoms may be under-reported or reported unreliably.
- Living alone or social isolation — delays recognition and correction of an evolving medication problem.
- Alcohol use in combination with any sedating or antihypertensive medication.
Red Flags & Refer
Most dizziness, including most medication-induced dizziness, is not an emergency — but any of the following changes the plan from "structured review" to "urgent assessment":
- Sudden, severe vertigo accompanied by a new focal neurologic deficit (diplopia, dysarthria, dysphagia, facial droop, limb weakness/numbness) or an inability to stand or walk unassisted — treat as a possible posterior circulation stroke or TIA until proven otherwise.[10]
- Continuous (not positional) vertigo lasting hours to days rather than brief triggered episodes — this pattern (acute vestibular syndrome) needs its own urgent work-up rather than a routine dizziness review.
- Chest pain, palpitations, or syncope accompanying the dizziness — evaluate urgently for a cardiac cause (arrhythmia, structural disease, acute coronary syndrome) with an ECG.
- A sudden, severe ("thunderclap" or "worst of my life") headache accompanying the dizziness.
- A significant fall or head injury associated with the dizziness, particularly in a patient on an anticoagulant or antiplatelet — assess for intracranial bleeding.
- Suspected digoxin toxicity — dizziness with visual changes (halos, altered colour perception), nausea, or a new arrhythmia — needs an urgent level and ECG.
- New or worsening tinnitus or imbalance during an aminoglycoside or vancomycin course, or with sustained high-dose salicylate use — vestibulotoxicity can progress to permanent injury if the causative drug is not stopped promptly; contact the prescriber urgently rather than waiting for a routine follow-up.
- New or worsening dizziness in an elderly or frail patient after a new medication or dose change — treat as a medication-induced dizziness/fall-risk problem warranting an urgent, not routine, medication review, given the well-documented gap between how often this happens and how often it is properly worked up in practice.[1]
The HINTS exam — for continuous vertigo, not for a routine dizziness review
The HINTS exam (Head-Impulse, Nystagmus, Test-of-Skew) is a 3-part bedside oculomotor exam developed to distinguish a peripheral cause (typically vestibular neuritis) from a central cause (typically a cerebellar or brainstem stroke) in a patient with continuous vertigo, nausea, and unsteadiness lasting more than 24 hours. In a trained examiner's hands, a HINTS pattern fully consistent with a peripheral cause is more sensitive for excluding stroke than an early MRI with diffusion-weighted imaging obtained within the first 24-48 hours.[10] This is a different clinical scenario from the brief, triggered, or medication-related dizziness this chapter otherwise covers — reserve it for genuinely continuous vertigo with a possible central cause, and see the Benign Paroxysmal Positional Vertigo chapter for the full HINTS technique and interpretation table.
Assessment & Diagnosis
History
Ask the patient to describe the sensation in their own words rather than accepting the word "dizzy" at face value — this single step is one of the quality indicators found to be inconsistently documented in routine practice, and is significantly associated with reaching a clinical diagnosis.[1] Establish timing (episodic vs. continuous), triggers (positional, orthostatic, spontaneous, exertional), and associated symptoms (hearing change, chest pain, headache, weakness) using the TiTrATE framework alongside the 4-category symptom description.[4] Take a complete medication history including OTC products, herbal/supplement use, and alcohol, and ask specifically and directly: "Did this start, or get worse, after starting a new medication or a dose change?" — correlating the timeline against the pharmacy fill/refill record where available. Ask about falls in the preceding year and about depression/anxiety symptoms, both flagged as under-documented quality indicators in the same Canadian audit.[1]
Orthostatic vital signs — the technique matters
Orthostatic hypotension is defined by international consensus as a systolic blood pressure drop of at least 20 mmHg, or a diastolic drop of at least 10 mmHg, within 3 minutes of standing.[5]
- Have the patient rest supine for at least 5 minutes before the first measurement.
- Measure blood pressure and heart rate supine.
- Have the patient stand (or, if standing is not safe, sit upright with legs dependent), and measure blood pressure and heart rate at 1 minute and again at 3 minutes after the position change.[11]
- Ask specifically about symptoms (light-headedness, visual dimming, near-faint) at each standing measurement, not only at the end.
- A measured drop meeting the criteria above, especially if it reproduces the patient's symptom, confirms orthostatic hypotension as a contributor — proceed to Choose Initial Treatment for the medication-adjustment approach.
Structured medication screening tools
Apply the medication list against 2 complementary structured tools rather than relying on memory or a single obvious suspect:
- The 2023 AGS Beers Criteria flags specific drugs and classes as potentially inappropriate in older adults because of CNS effects, anticholinergic burden, or hypoglycemia risk — including benzodiazepines, non-benzodiazepine sedative-hypnotics, first-generation antihistamines, tricyclic antidepressants, and certain sulfonylureas (notably glyburide).[6]
- STOPP/START version 3 adds explicit criteria for drugs causing orthostatic hypotension and fall risk in older people, alongside START criteria flagging when a needed medication may have been inappropriately withheld — a useful check against over-correcting in the other direction.[9]
Both tools are decision aids requiring clinical judgment, not automatic stop/start instructions — a flagged drug may still be the right choice for a specific patient once benefits and alternatives are weighed.
Physical examination
Beyond orthostatic vital signs: a basic gait assessment (does the patient rise from a chair and walk safely without assistance?), a cardiac exam (rate, rhythm, murmurs), a screening neurologic exam, and a vision check. Look for medication-specific signs — nystagmus or ataxia suggesting phenytoin toxicity, miosis suggesting opioid effect, or a resting tremor suggesting Parkinsonism contributing to disequilibrium.
Investigations
A point-of-care glucose is quick and directly relevant whenever the pattern is presyncope-like in a patient on insulin or a sulfonylurea. Basic bloodwork (CBC, electrolytes, renal function) helps assess drug clearance and rule out anemia or a metabolic contributor. Obtain an ECG if a cardiac cause is suspected or if a newly started or increased medication affects the QTc. Check a drug level where relevant and available (phenytoin, digoxin, an aminoglycoside) rather than assuming toxicity from the history alone.
Differential diagnosis by category
| Category | Non-medication causes to consider | Medication-related causes to consider |
|---|---|---|
| Vertigo | BPPV (see the dedicated chapter), vestibular neuritis/labyrinthitis, Ménière's disease, vestibular migraine, central (stroke/TIA — see Red Flags) | Aminoglycoside or high-dose salicylate vestibulotoxicity |
| Presyncope | Arrhythmia, structural cardiac disease, vasovagal syncope, volume depletion, anemia | Orthostatic hypotension from antihypertensives/diuretics/alpha-blockers/TCAs; hypoglycemia from insulin/sulfonylureas |
| Disequilibrium | Peripheral neuropathy, Parkinsonism, cervical spondylosis, visual impairment, cerebellar disease | Sedatives, opioids, anticholinergics, antiepileptics |
| Nonspecific/psychogenic | Anxiety, hyperventilation, persistent postural-perceptual dizziness, depression | Cumulative polypharmacy burden without 1 clear culprit |
Treatment Targets
- Classify the symptom by quality (vertigo/presyncope/disequilibrium/nonspecific) and by timing/triggers to organize the differential efficiently.
- Screen explicitly for red flags before assuming a benign or medication-related cause.
- Identify every medication plausibly contributing, by mechanism, rather than stopping at the first suspect found.
- Correct the reversible medication contribution — through dose reduction, timing change, or substitution — in collaboration with the prescriber, without inappropriately withholding a medication the patient genuinely needs.
- Apply structured screening tools (Beers Criteria, STOPP/START) to the whole medication list, not only to the drug the patient suspects.
- Reduce fall risk through both the medication correction and non-pharmacologic falls-prevention counselling.
- Avoid 2 opposite errors: reflexively adding a vestibular suppressant instead of reviewing medications, and abruptly stopping a needed medication without a taper or follow-up plan.
- Confirm the original indication for any adjusted medication remains adequately treated after the change.
Choose Initial Treatment
The treatment is medication review and adjustment — not adding a new drug
When dizziness is identified as medication-induced, the correct first-line action is identifying and adjusting the causative agent in collaboration with the prescriber — not reaching for a vestibular suppressant or another symptomatic drug on top of the problem. 1st step, every mechanism confirm the temporal relationship, apply the Beers Criteria/STOPP-START screen, and involve the prescriber before making any change.[6][9]
Orthostatic hypotension
Preferred approach dose reduction, a timing change (e.g., moving a diuretic or alpha-blocker dose to bedtime, or dosing an antihypertensive so its peak effect does not coincide with the patient's most active hours), or substitution to a lower-OH-risk agent within the same therapeutic class.[11] Situational when the drug is genuinely needed for its primary indication (e.g., heart failure, resistant hypertension), accept a monitored, modest symptom with close follow-up rather than under-treating the underlying condition — this is a judgment call made with the prescriber, not a default to stop.
Vestibulotoxicity
Act promptly for a suspected aminoglycoside, vancomycin, or high-dose salicylate contribution — check levels where available, and contact the prescriber urgently, since delay risks permanent injury for the aminoglycoside/vancomycin combination specifically. Reversible salicylate- and quinine-induced vestibulotoxicity typically resolves within days of stopping the drug — this is a genuinely reassuring, actionable teaching point distinct from aminoglycoside risk.
Sedation and CNS depression
Do not stop a benzodiazepine or another chronically used sedative abruptly — withdrawal itself causes rebound anxiety, insomnia, and seizure risk. Preferred approach a structured, gradual taper individualized to the patient, following the Bruyère Research Institute/Deprescribing.org benzodiazepine receptor agonist deprescribing guideline rather than an ad hoc reduction.[12] For a first-generation antihistamine or anticholinergic used for sleep, allergy, or bladder symptoms, a lower-burden substitute (a second-generation antihistamine, or a non-anticholinergic bladder agent) is often available — discuss with the prescriber rather than simply continuing by default.
Hypoglycemia
Preferred approach adjust insulin or sulfonylurea dosing and timing relative to meals and activity; where glycemic control allows, a lower hypoglycemia-risk regimen (e.g., metformin-based rather than a sulfonylurea, or gliclazide rather than glyburide) is a reasonable substitution to discuss with the prescriber.
Polypharmacy without 1 clear culprit
Preferred approach a full structured deprescribing review against Beers Criteria and STOPP/START, addressing cumulative burden rather than searching indefinitely for a single drug to blame.[6][9][8]
Non-Pharmacologic Treatment
Falls-prevention counselling
Non-pharmacologic falls-prevention measures apply regardless of the specific medication contribution, and are core, not optional, in every patient with dizziness and any fall risk:
- Home safety review — adequate lighting (including nightlights), removal of loose rugs and clutter from walkways, grab bars in the bathroom, and non-slip mats.[13]
- Appropriate, well-fitting footwear with good tread; avoid loose slippers and walking in socks alone.
- Vision and hearing checks, since both are redundant inputs the balance system relies on.
- Adequate hydration, and moderation of alcohol intake specifically when combined with a sedating or antihypertensive medication.
- Referral for a structured exercise, balance, or physiotherapy program where fall risk is elevated — this is one of the best-supported non-pharmacologic interventions for reducing falls in older adults.[13]
- Hip protectors for patients at particularly high fracture risk.
Orthostatic countermeasures
- Rise in stages: sit at the edge of the bed for a moment before standing, rather than going straight from lying to standing.
- Ankle pumps, calf raises, or hand-clenching for 30 seconds before standing to promote venous return.
- Graduated compression stockings for patients with persistent orthostatic hypotension not fully explained or corrected by medication adjustment.
- Adequate salt and fluid intake where not contraindicated by heart failure or significant renal disease — confirm this is appropriate for the individual patient before advising it.
Structured medication review, in practice
- Ask the patient (or a caregiver) to bring every medication and supplement bottle in — including OTC products — for a genuine "brown-bag" review rather than relying on a chart list that may be out of date.
- Build a simple timeline correlating symptom onset against every new drug start and dose change over the preceding weeks to months, rather than assuming the most recently started drug is automatically the cause.
- Screen the full list against the Beers Criteria and STOPP/START, then discuss flagged items with the prescriber as a collaborative recommendation, not a unilateral change.
Patient education
- Explain the specific mechanism identified (orthostatic, sedation, vestibulotoxic, hypoglycemic) in plain language — patients engage better with a change they understand the reason for.
- Never stop a prescribed medication on your own because of a suspicion it is causing dizziness — this is the single most important counselling point, since abrupt discontinuation of some of these drugs (clonidine, benzodiazepines) carries its own genuine, separate risk.
- Rise slowly from lying or sitting, especially first thing in the morning and after meals.
- Keep a simple symptom/timing diary if the cause is not immediately obvious — this becomes genuinely useful data at the next review.
- Know the specific red flags that warrant urgent care rather than waiting for the next scheduled visit (see Red Flags & Refer).
- Bring an updated medication list to every appointment, including any new OTC or supplement purchase.
Special Populations
Older adults and frailty
This is the population this chapter is written for. Physiologic changes with age — reduced baroreceptor sensitivity, reduced renal and hepatic drug clearance, increased body-fat-to-lean-mass ratio prolonging the half-life of lipophilic drugs (many benzodiazepines), and blunted thirst — all raise both the likelihood and the severity of medication-induced dizziness at doses tolerated well in a younger adult. Preferred approach apply the Beers Criteria and STOPP/START to every medication list in this group, not only when dizziness is the presenting complaint, since these are the tools consistently associated in the Canadian literature with a lower rate of recurrent falls when properly applied.[6][9][8] Avoid benzodiazepines and other sedative-hypnotics as first choice for insomnia, agitation, or delirium in this group — this is a direct Choosing Wisely Canada geriatrics recommendation.[7]
Diabetes
Autonomic neuropathy blunts the normal compensatory heart-rate and vasoconstrictive response to standing, compounding any antihypertensive's own orthostatic hypotension risk on top of the direct hypoglycemia risk from insulin or a sulfonylurea. Hypoglycemia unawareness — reduced or absent warning symptoms before a low blood glucose — is more common with longstanding diabetes and with recurrent hypoglycemia itself, so dizziness may be a late rather than early sign.
Renal impairment
Reduces clearance of gabapentin, pregabalin, most opioids and their active metabolites, many benzodiazepine metabolites, and the aminoglycosides — raising effective drug exposure without any dose change having been made. Confirm renal dose adjustment specifically for gabapentin and pregabalin, since this is one of the most common and most correctable contributors to excess dizziness in an older adult with reduced kidney function.
Hepatic impairment
Reduces clearance of most benzodiazepines and opioids, prolonging sedative effect; oxazepam and lorazepam are metabolized by glucuronidation rather than hepatic oxidation and are relatively (not absolutely) preferred when a benzodiazepine is genuinely needed in significant hepatic impairment.
Pregnancy
Some degree of orthostatic intolerance is physiologic in pregnancy given normal hemodynamic changes, and is not itself a medication effect in most cases. Avoid unnecessary medication changes for mild, positional, non-red-flag dizziness in pregnancy; confirm any medication adjustment against the drug's own Drug Database entry and the relevant condition-specific chapter for pregnancy-specific guidance.
Parkinson disease
Levodopa-carbidopa and other dopaminergic therapy can itself cause or worsen orthostatic hypotension, on top of the disease's own autonomic involvement — dizziness in this population often needs input from the treating neurologist rather than a simple dose reduction, since under-treating the motor symptoms carries its own real cost.
Monitoring & Follow-Up
Reassess within days to a couple of weeks after any medication adjustment made for dizziness — confirm the symptom has genuinely improved, and just as importantly, confirm the original indication for the adjusted drug remains adequately controlled (blood pressure still at goal after a diuretic dose reduction, glycemic control still adequate after a hypoglycemia-risk change, anxiety/insomnia still manageable during a benzodiazepine taper). Repeat orthostatic vital signs at follow-up rather than relying on symptom report alone.
Complications of unaddressed medication-induced dizziness
- Falls and fracture — the most consequential complication, with hip fracture in particular carrying a real risk of lost independence and mortality in older adults; this is the central reason falls-prevention counselling is core to this chapter, not an afterthought.
- Motor vehicle and other accidents — sedating medications specifically raise this risk; counsel accordingly, particularly during any dose titration.
- Medication nonadherence — a patient who attributes dizziness to a needed drug may simply stop taking it without telling anyone, leaving the original condition (hypertension, arrhythmia, diabetes) undertreated; a proactive medication review headed off before this happens is materially better than reacting after the fact.
- A missed serious diagnosis — attributing dizziness to "probably the medication" without adequately screening for red flags risks missing a genuine stroke, cardiac event, or other emergent cause; medication causation and a serious underlying cause are not mutually exclusive possibilities and both need to be actively excluded.
- Loss of confidence and activity avoidance — fear of a further dizzy spell or fall can lead to reduced activity, deconditioning, and social isolation, which in turn worsens both physical fall risk and mood — a cycle worth naming explicitly to the patient.
Common Errors to Avoid
- Reflexively reaching for a vestibular suppressant (an antihistamine or benzodiazepine) instead of reviewing the medication list for a reversible cause.
- Abruptly stopping a medication suspected of causing dizziness without a taper plan — clonidine and chronic benzodiazepine use both carry genuine, separate risks from abrupt discontinuation.
- Measuring "orthostatic vitals" as a single supine-to-standing check without the correct timing (5 minutes supine, then 1 and 3 minutes standing), which can miss a delayed drop.
- Stopping the medication-review process after finding 1 plausible culprit in a patient on multiple relevant drugs, rather than screening the whole list.
- Not asking specifically about OTC products, supplements, and alcohol — patients reliably under-report these unless asked directly.
- Assuming dizziness is medication-related without first screening for red flags — the 2 are not mutually exclusive, and a genuine stroke or cardiac event can coincide with an unrelated medication change.
- Missing hypoglycemia as a cause in a patient on insulin or a sulfonylurea because the presentation looks like ordinary light-headedness rather than a classic hypoglycemic episode.
- Failing to apply a structured screening tool (Beers Criteria, STOPP/START) and relying instead on memory or the most obviously "suspicious-looking" drug.
- Treating polypharmacy-driven cumulative risk as though it must have 1 identifiable culprit drug, rather than addressing the overall burden.
- Not closing the loop with a follow-up visit to confirm both symptom improvement and that the original indication for any adjusted drug remains adequately treated.
Clinical Decision Algorithm
Drug Tables
How to use this table: this catalogues medications commonly implicated in dizziness, organized by the 4 mechanisms discussed in Recognize the Condition, to support a structured medication review — it is not a treatment menu. Doses shown are typical adult doses only and require patient-specific confirmation, including renal/hepatic adjustment. Select any drug name to open its complete Pharmasist Drug Database page.
Mechanism 1 — Orthostatic Hypotension: Antihypertensives, Diuretics, Alpha-Blockers, TCAs
Confirm with correctly performed orthostatic vital signs (supine 5 minutes, then standing at 1 and 3 minutes) before attributing dizziness to this mechanism.
| Drug | Typical dosing | Dizziness-relevant adverse effect | Drug interactions | Management comment |
|---|---|---|---|---|
| Hydrochlorothiazide | Adults: 12.5-25 mg PO daily | Dizziness on standing, dehydration, hyponatremia | Additive orthostatic hypotension with other antihypertensives | Dose-related risk; check standing BP after any increase. |
| Furosemide | Adults: 20-80 mg PO daily, higher in renal/cardiac disease | Volume-depletion-driven orthostatic hypotension; electrolyte derangement; ototoxic at high IV doses | Additive orthostatic hypotension with other antihypertensives; additive ototoxicity with aminoglycosides | The one agent in this table with both orthostatic and vestibulotoxic potential — review both. |
| Doxazosin | Adults: 1-8 mg PO daily | First-dose and dose-increase orthostatic hypotension, syncope | Additive orthostatic hypotension with other antihypertensives and PDE5 inhibitors | Take the first dose and any increase at bedtime; rise slowly for several days after a change. |
| Tamsulosin | Adults: 0.4-0.8 mg PO daily | Orthostatic hypotension, particularly with the first dose | Additive orthostatic hypotension with antihypertensives and PDE5 inhibitors | Prescribed for BPH in older men often already on an antihypertensive — check for a doubled risk. |
| Ramipril | Adults: 2.5-10 mg PO daily | Orthostatic hypotension especially after the first dose or when a diuretic is added; hyperkalemia | Additive hypotension/hyperkalemia with other RAAS agents and potassium-sparing diuretics | Risk rises sharply if a diuretic is started concurrently or the patient becomes volume-depleted. |
| Nifedipine (extended-release) | Adults: 30-90 mg PO daily | Peripheral edema, flushing, dose-related orthostatic hypotension | Additive orthostatic hypotension with other antihypertensives | Short-acting formulations carry a materially higher risk than extended-release — confirm formulation. |
| Clonidine | Adults: 0.1-0.3 mg PO twice daily | Prominent orthostatic hypotension and sedation together; rebound hypertension with abrupt discontinuation | Additive hypotension/sedation with other antihypertensives and CNS depressants | Never stop abruptly — taper to avoid a rebound hypertensive crisis. |
| Amitriptyline | Adults: 10-25 mg PO at bedtime | Orthostatic hypotension from alpha-1 blockade, plus anticholinergic and sedative effects | Additive hypotension/sedation/anticholinergic burden with other CNS depressants and anticholinergics | Flagged by the Beers Criteria; if a TCA is truly needed, nortriptyline carries a lower burden. |
| Nortriptyline | Adults: 10-25 mg PO at bedtime | Lower, but still present, orthostatic and anticholinergic burden than amitriptyline | Same class interactions as amitriptyline | The comparatively safer TCA choice when a TCA is genuinely required — not a "safe" drug in absolute terms. |
Mechanism 2 — Vestibulotoxicity: Aminoglycosides, Loop Diuretics, High-Dose Salicylates
Risk rises with cumulative dose, duration beyond about 7-10 days, and renal impairment. Ask specifically about tinnitus and imbalance during any course of these agents.
| Drug | Typical dosing | Dizziness-relevant adverse effect | Drug interactions | Management comment |
|---|---|---|---|---|
| Gentamicin | Adults: Dosed per level and renal function | Dose- and duration-related, potentially irreversible cochlear and vestibular toxicity | Additive nephro/ototoxicity with other nephrotoxins/ototoxic drugs (loop diuretics, vancomycin) | Monitor levels; ask about tinnitus/imbalance during any course. |
| Tobramycin | Adults: Dosed per level and renal function | Same aminoglycoside vestibulotoxicity profile as gentamicin | Same additive nephro/ototoxicity | Inhaled use in cystic fibrosis still carries measurable systemic ototoxicity risk with prolonged courses. |
| Streptomycin | Adults: Dosed per weight and renal function | Vestibulotoxicity, historically the aminoglycoside most associated with vestibular (vs. cochlear) injury | Same additive nephro/ototoxicity | Vestibular toxicity here is classically more prominent than hearing loss. |
| Vancomycin | Adults: Dosed per level and renal function | Ototoxicity, particularly at high trough levels or with concurrent aminoglycoside use | Additive nephro/ototoxicity with aminoglycosides and loop diuretics | Not itself an aminoglycoside, but real synergistic ototoxicity risk when combined with one. |
| Acetylsalicylic acid | Adults: Sustained high analgesic/anti-inflammatory dosing, not typical low-dose cardioprotective use | Tinnitus as an early warning sign, followed by reversible hearing loss and imbalance at sustained high doses | Additive GI/bleeding risk with anticoagulants | Genuinely reversible within days of stopping — distinct from the aminoglycoside entries above. |
| Quinine | Adults: Per product labelling; not recommended for routine leg-cramp use | Cinchonism: tinnitus, vertigo, headache, visual disturbance | Additive QTc prolongation and bleeding risk with warfarin | Given the poor risk-benefit ratio for leg cramps specifically, often an opportunity to deprescribe entirely. |
Mechanism 3 — Sedation and CNS Depression: Benzodiazepines, Opioids, Anticholinergics/Antihistamines, Antiepileptics
Flagged collectively by the AGS Beers Criteria and, for sedative-hypnotics specifically, by Choosing Wisely Canada's geriatrics recommendation. A structured taper, not abrupt discontinuation, applies to chronic benzodiazepine use.
| Drug | Typical dosing | Dizziness-relevant adverse effect | Drug interactions | Management comment |
|---|---|---|---|---|
| Diazepam | Adults: Variable, individualized | Prolonged sedation, ataxia, disproportionate fall risk from a long half-life and active metabolites | Additive CNS depression with alcohol, opioids, other sedatives | Among the least suitable benzodiazepines for an older adult given its long duration of action. |
| Lorazepam | Adults: Variable, individualized | Sedation, ataxia, fall risk despite a shorter half-life than diazepam | Additive CNS depression with other sedatives | Still flagged by the Beers Criteria; a shorter half-life reduces but does not eliminate the risk. |
| Zopiclone | Adults: 3.75-7.5 mg PO at bedtime | Next-day sedation, ataxia, and fall risk comparable to a benzodiazepine | Additive CNS depression with other sedatives | Choosing Wisely Canada's geriatrics recommendation groups this with benzodiazepines for older adults. |
| Morphine | Adults: Variable, individualized | Sedation and dizziness from both direct CNS effect and opioid-related orthostatic hypotension | Additive CNS depression with benzodiazepines and other sedatives | Dizziness is most pronounced at initiation or a dose increase — reassess after every titration. |
| Hydromorphone | Adults: Variable, individualized | Similar sedation/orthostatic profile to morphine | Additive CNS depression with other sedatives | Preferred over morphine in renal impairment for more predictable metabolite handling; dizziness risk itself is not meaningfully lower. |
| Diphenhydramine | Adults: 25-50 mg PO | Prominent anticholinergic burden (confusion, dizziness, dry mouth, urinary retention) on top of sedation | Additive anticholinergic/sedative burden with other anticholinergics and CNS depressants | Widely available OTC as a sleep aid and in cold products — ask about it explicitly. |
| Hydroxyzine | Adults: 10-25 mg PO | Same anticholinergic/sedation combination as diphenhydramine | Same additive risk | Sometimes prescribed for anxiety or itch without the anticholinergic burden being reconsidered. |
| Dimenhydrinate | Adults: 50-100 mg PO/IM/IV/PR every 4-6 hours PRN | Sedation and anticholinergic effects; can itself perpetuate imbalance with prolonged use | Additive CNS depression with other sedatives | Marketed to treat dizziness/nausea but is itself sedating and anticholinergic — see the BPPV chapter's discussion of its limits. |
| Oxybutynin | Adults: 5 mg PO 2-3 times daily, or extended-release | Anticholinergic burden including dizziness and confusion, beyond its intended bladder effect | Additive anticholinergic burden with other anticholinergics | A less anticholinergic bladder agent is often available and worth discussing with the prescriber. |
| Gabapentin | Adults: 100-300 mg PO at bedtime, titrated, renally adjusted | Dizziness and sedation are dose-limiting effects, worsened by renal accumulation | Additive CNS depression with opioids and other sedatives | Renal dose adjustment is frequently missed and highly correctable. |
| Phenytoin | Adults: Dosed to a therapeutic serum level | Dose-related cerebellar/vestibular toxicity — nystagmus, ataxia, dizziness — tracking with serum level | Numerous CYP-mediated interactions altering phenytoin levels | New dizziness in a patient on phenytoin should prompt a level check before assuming an unrelated cause. |
Mechanism 4 — Hypoglycemia: Insulin and Sulfonylureas
Hypoglycemia unawareness is more common in older adults and with autonomic neuropathy, so classic warning symptoms may be blunted.
| Drug | Typical dosing | Dizziness-relevant adverse effect | Drug interactions | Management comment |
|---|---|---|---|---|
| Insulin (all types) | Adults: Individualized | Hypoglycemia: dizziness, presyncope, sweating, confusion | Additive hypoglycemia risk with sulfonylureas and alcohol | Ask specifically about timing relative to meals and activity. |
| Glyburide | Adults: 2.5-10 mg PO daily or divided | The highest hypoglycemia risk among the sulfonylureas, sometimes prolonged and severe, particularly in renal impairment | Additive hypoglycemia risk with insulin, alcohol, other glucose-lowering drugs | Flagged by the Beers Criteria; gliclazide is a comparatively safer within-class alternative. |
| Gliclazide | Adults: 40-320 mg PO daily; modified-release available | Lower, but still real, hypoglycemia risk than glyburide | Same additive hypoglycemia risk | A reasonable substitute when a sulfonylurea is genuinely needed and glyburide is flagged on review. |
| Metformin | Adults: 500-2000 mg PO daily, divided | Does not itself cause hypoglycemia as monotherapy | None causing additive hypoglycemia | The reference point for a lower hypoglycemia-risk alternative where glycemic control allows. |
References
- Assessment of dizziness among older patients at a family practice clinic: a chart audit study — BMC Family Practice (Kwong EC, Pimlott NJ). BMC Fam Pract 2005;6:2
- An approach to the dizzy patient — Neurology (Drachman DA, Hart CW). Neurology 1972;22(4):323-334
- Dizziness: Approach to Evaluation and Management — American Family Physician (Muncie HL, Sirmans SM, James E). Am Fam Physician 2017;95(3):154-162
- TiTrATE: A Novel, Evidence-Based Approach to Diagnosing Acute Dizziness and Vertigo — Neurologic Clinics (Newman-Toker DE, Edlow JA). Neurol Clin 2015;33(3):577-599
- Consensus statement on the definition of orthostatic hypotension, neurally mediated syncope and the postural tachycardia syndrome — Clinical Autonomic Research, American Autonomic Society and European Federation of Autonomic Societies (Freeman R, Wieling W, Axelrod FB, et al.). Clin Auton Res 2011;21(2):69-72
- American Geriatrics Society 2023 updated AGS Beers Criteria for potentially inappropriate medication use in older adults — Journal of the American Geriatrics Society, AGS Beers Criteria Update Expert Panel. J Am Geriatr Soc 2023;71(7):2052-2081
- Geriatrics: Fifteen Things Physicians and Patients Should Question — Choosing Wisely Canada, Canadian Geriatrics Society. Choosing Wisely Canada, Geriatrics recommendation list
- Medications & Polypharmacy Influence on Recurrent Fallers in Community: a Systematic Review — Canadian Geriatrics Journal (Ming Y, Zecevic A). Can Geriatr J 2018;21(1):14-25
- STOPP/START criteria for potentially inappropriate prescribing in older people: version 3 — European Geriatric Medicine (O'Mahony D, Cherubini A, Renom Guiteras A, et al.). Eur Geriatr Med 2023;14(4):625-632
- HINTS to Diagnose Stroke in the Acute Vestibular Syndrome: Three-Step Bedside Oculomotor Examination More Sensitive Than Early MRI Diffusion-Weighted Imaging — Stroke (Kattah JC, Talkad AV, Wang DZ, Hsieh YH, Newman-Toker DE). Stroke 2009;40(11):3504-3510
- Orthostatic Hypotension: A Practical Approach — American Family Physician (Kim MJ, Farrell J). Am Fam Physician 2022;105(1):39-49
- Deprescribing benzodiazepine receptor agonists: Evidence-based clinical practice guideline — Canadian Family Physician, Bruyère Research Institute (Pottie K, Thompson W, Davies S, et al.). Can Fam Physician 2018;64(5):339-351
- Fall Prevention: Risk Assessment and Management for Community-Dwelling Older Adults — BC Guidelines, British Columbia Ministry of Health. BC Ministry of Health, BC Guidelines, 2021
Professional reference only. Apply clinical judgment and verify patient-specific decisions against current authoritative guidance and product information.