Calcitonin (Calcimar)

1. Health Canada Product Monograph — Calcitonin

• Calcitonin is used to treat symptomatic Paget's disease of bone in patients who cannot use or have not responded to other treatments, and to help lower dangerously high blood calcium levels as part of a broader treatment plan for hypercalcemia.

• Animal studies with calcitonin showed reduced fetal birth weight, and there isn't enough human data to rule out risk to the developing baby, so it should only be used in pregnancy if the potential benefit clearly justifies the possible risk.

• Calcitonin has been shown to suppress milk production in animal studies and should not be used by women who are breastfeeding.

• No calcitonin-specific dosing changes are outlined for older adults, but as with any calcium-lowering therapy, closer monitoring of calcium levels is prudent in elderly patients.

• The safety of calcitonin has not been established in children, so its use is generally not recommended in this age group.

• Nausea, with or without vomiting, is the most common calcitonin side effect, along with flushing of the face and hands, injection site redness or swelling, and a metallic or salty taste.

Serious side effects require immediate discussion with the prescriber or emergency care.

• Calcitonin can rarely cause serious allergic reactions such as bronchospasm, throat swelling, or anaphylaxis, and can also trigger hypocalcemic tetany with muscle cramping and twitching from low calcium; long-term calcitonin use has also been linked to an increased risk of certain cancers, so treatment is generally limited to the shortest effective duration.

• Patients with a history of allergies or suspected sensitivity to calcitonin should be skin tested before starting treatment, and anyone on chronic calcitonin therapy should have periodic blood and urine monitoring.

• Calcitonin should not be used by anyone with a known hypersensitivity to calcitonin-salmon or to any ingredient in the injection.

• Calcitonin can lower blood lithium levels, so lithium doses may need adjustment and monitoring when the two are used together.

• No specific food interactions have been identified with injectable calcitonin.

• Calcitonin is given by intramuscular or subcutaneous injection as directed by a healthcare professional; it is not taken orally and has no specific time-of-day requirement.

• Calcitonin should be kept refrigerated between 2 and 8 degrees Celsius, though it remains stable at room temperature for up to two weeks if refrigeration isn't available.

• Calcitonin is an injectable hormone therapy used to manage Paget's disease of bone and to help bring down severely elevated blood calcium, and because of a link to increased cancer risk with prolonged use, it's typically prescribed for the shortest time needed at the lowest effective dose.