Calcitonin100 IU/ml

Calcitonin is a polypeptide hormone (derived from Calcitonin, more potent per unit than human calcitonin) that inhibits osteoclast-mediated bone resorption. Its approved and evidence-based uses include:

• Paget's disease of bone (FDA-approved): Used in symptomatic, moderate-to-severe Paget's disease to reduce bone turnover and relieve bone pain, particularly in patients who cannot use or have not responded to bisphosphonates.
• Hypercalcemia of malignancy (FDA-approved, adjunctive): Used as an adjunct to more definitive therapy (e.g. intravenous fluids, bisphosphonates) for rapid, short-term lowering of serum calcium.
• Postmenopausal osteoporosis (FDA-approved, but now second-line/limited use): Indicated for women more than 5 years postmenopausal, generally reserved for patients unable to use other osteoporosis therapies (e.g. bisphosphonates, hormone therapy) because long-term use has been associated with a small increased risk of malignancy in some analyses; regulatory agencies now recommend restricting duration of use in this indication.
• Acute bone loss from sudden immobilization (guideline-supported, short-term): Occasionally used short-term for immobilization-related bone loss, e.g. after fracture or spinal cord injury.

Use of Calcitonin beyond short courses should be individualized by a physician, weighing benefit against the malignancy-risk signal described under Precautions.

Each formulation of Salmon Calcitonin contains synthetic calcitonin identical in sequence to that produced by salmon, supplied as an intranasal spray or as a solution for subcutaneous/intramuscular injection, depending on the marketed product and strength.

Calcitonin is a 32-amino-acid polypeptide hormone that mimics the action of calcitonin, a hormone normally secreted by the parafollicular (C) cells of the thyroid gland. Salmon-derived calcitonin is used pharmaceutically because it is significantly more potent and has a longer duration of action than human calcitonin. It is available as a nasal spray and as an injectable solution.

Calcitonin belongs to the therapeutic class of calcitonin analogues / bone resorption inhibitors (calcium regulating hormones), used in metabolic bone disorders.

Salmon Calcitonin binds to calcitonin receptors on osteoclasts, directly inhibiting osteoclastic bone resorption and reducing the rate of bone turnover. This lowers serum calcium and phosphate concentrations derived from bone. It also has a mild direct renal effect, increasing renal excretion of filtered calcium, phosphate, and sodium.

Salmon-derived calcitonin binds calcitonin receptors with higher affinity and is metabolized more slowly than human calcitonin, giving it greater potency per unit dose. Onset of the hypocalcemic effect occurs within hours; analgesic effects in Paget's disease and bone pain may take days to weeks to become apparent.

Calcitonin nasal spray should be administered into one nostril daily, alternating nostrils each day, with the head upright; prime the pump before first use as directed in the product leaflet. Injectable Calcitonin is given by subcutaneous or intramuscular injection, with injection sites rotated to reduce local reactions. A skin test may be considered by the physician before the first dose in patients with suspected sensitivity, per some product labeling. Do not alter the dose or route without medical advice.

Calcitonin has relatively few well-established clinically significant drug interactions compared to many medicines, but the following should be noted:

• Lithium: Calcitonin may reduce plasma lithium concentrations by an unclear mechanism; lithium levels should be monitored if used concurrently with Calcitonin.
• Other calcium-lowering agents (e.g. bisphosphonates): Concomitant use with other agents that lower serum calcium may have additive hypocalcemic effects; calcium levels should be monitored.

Inform the physician of all other medicines being taken before starting Calcitonin.

Common and important side effects of Calcitonin include:

• Nasal spray: Nasal irritation, rhinitis, nasal congestion, epistaxis (nosebleed), sinusitis, and other local nasal symptoms are common.
• Injection: Nausea (especially with initial doses, usually diminishing with continued use), flushing of the face and hands, injection-site reactions, and local inflammation.
• General: Headache, dizziness, urinary frequency, and rarely hypersensitivity reactions ranging from skin rash to (uncommonly) anaphylaxis.
• Tachyphylaxis: A gradual reduction in effectiveness may occur with prolonged use of Calcitonin.

There is limited controlled data on the use of Calcitonin in human pregnancy. As calcitonin is a large peptide hormone, placental transfer is expected to be minimal, but Calcitonin should be used during pregnancy only if clearly needed and if the potential benefit justifies the potential risk to the fetus; consult a physician before use.

It is not known whether Calcitonin is excreted in human breast milk. Caution is advised, and a physician should be consulted to weigh the benefits of treatment against potential risk to a nursing infant before using Calcitonin while breastfeeding.

The following precautions apply to the use of Calcitonin:

• Malignancy risk signal with long-term use: Some pooled analyses have identified a small increased risk of malignancy associated with long-term use of Calcitonin, particularly in the osteoporosis indication. Regulatory authorities have advised limiting long-term use, especially for osteoporosis, to situations where the benefit clearly outweighs this risk and no suitable alternative therapy exists; treatment duration should be discussed with the prescriber.
• Hypersensitivity/allergic reactions: Because Calcitonin is a salmon-derived protein, allergic reactions including rare anaphylaxis can occur; a skin test may be considered before the first dose in at-risk patients per some product labeling.
• Tachyphylaxis: Declining effectiveness can occur with prolonged use; periodic reassessment of response is recommended.
• Nasal irritation: With the nasal spray formulation, periodic examination of the nasal mucosa is advisable, especially with long-term use.
• Calcium monitoring: Serum calcium should be monitored during treatment, particularly when Calcitonin is used for hypercalcemia of malignancy, to guide dose adjustment and avoid hypocalcemia.

Overdose with Calcitonin may cause nausea and vomiting; theoretically, excessive doses could lower serum calcium and cause symptoms of hypocalcemia (e.g. muscle cramps, tingling). If an overdose of Calcitonin is suspected, seek immediate medical attention or contact a poison control center/emergency services rather than attempting to manage it at home.

Store injectable formulations of Calcitonin in a refrigerator (2-8°C) and protect from light; do not freeze. Nasal spray should be stored in a refrigerator prior to first use; once in use, follow the product-specific in-use storage instructions (commonly upright at room temperature for a limited number of weeks). Keep out of reach of children.

Pediatric use: Safety and efficacy of Calcitonin in children have not been well established; use in children is generally limited to specific specialist-directed situations.

Elderly: Calcitonin is commonly used in elderly patients (e.g. for Paget's disease and osteoporosis); no specific dose adjustment is generally required, but renal and hepatic function should be considered.

Renal impairment: No specific dose adjustment is well established, but caution and monitoring are advised.

Hepatic impairment: No specific dose adjustment is well established, but caution and monitoring are advised.

Duration of treatment with Calcitonin depends on indication: hypercalcemia of malignancy is typically treated short-term as an adjunct until definitive therapy takes effect; Paget's disease treatment courses are individualized (often several months) with periodic reassessment; for osteoporosis, treatment duration should be kept as short as clinically appropriate given the malignancy-risk signal with long-term use, and continued use should be reviewed periodically with the prescriber.

Salmon Calcitonin is classified as a calcitonin analogue and bone resorption inhibitor (calcium-regulating hormone).

Salmon Calcitonin acts by binding calcitonin receptors on osteoclasts, directly inhibiting osteoclast activity and bone resorption, and by increasing renal excretion of calcium and phosphate, thereby lowering serum calcium levels and reducing bone turnover.

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Safety and efficacy of Calcitonin in pediatric patients have not been well established. Use in children should only occur under specialist supervision for specific, well-justified indications.