Naturally-occurring calcitonin is synthesised by parafollicular cells in the thyroid gland of mammals and the ultimobranchial gland of birds and fish. The potency of salmon calcitonin is standardised according to its ability to lower plasma calcium levels of rats as compared to the International Reference standard.

Pharmacology

Calcitonin is a polypeptide hormone produced by the ultimobranchial gland in non-mammalian vertebrates or by the mammalian thyroid parafollicular cells. It inhibits osteoclastic bone resorption and reduces bone turnover. It decreases tubular reabsorption and promotes renal excretion of Ca, Cl, Na, Mg, K and phosphate.

Each ml Salmon Calcitonin injection contains-

• 50 or 100 I.U. salcatonin (present as Polyacetate polyhydrate)
• Sodium acetate 0.2%
• Glacial acetic acid 0.2%
• Sodium chloride 0.75%

Salmon Calcitonin contains 32 amino-acids in linear sequence with a disulphide bridge at position 1 and 7 and a molecular weight of 3431.9 (free peptide). Salcatonin is a white or grey-tinged white amorphous powder. It is very soluble in water and very slightly soluble in alcohol.

Salmon Calcitonin is indicated in Active Paget's disease in patients who do not respond to alternative treatments or for whom such treatments are not suitable; Hypercalcaemia.

Intravenous (Adult)-

• Emergency treatment of hypercalcaemia: Up to 10 u/kg in 500 mL of sodium chloride 0.9% by slow IV infusion over at least 6 hr.

Parenteral (Adult)-

• Adjunct in hypercalcaemia: SC/IM: 4 u/kg 12 hrly, may increase after 1-2 days to 8 u/kg 12 hrly to max 8 u/kg 6 hrly after 2 days. Alternatively, 100 u every 6-8 hr, increased after 1-2 days to max 400 u every 6-8 hr.
• Paget's disease of bone: SC/IM: 50 u 3 times wkly to 100 u/day.

Nasal (Adult)-

• Nasal postmenopausal osteoporosis: 200 u/day, alternation nostrils everyday.

Hypersensitivity. Patients with hypocalcaemia.

GI disturbances, dizziness, flushing, tingling of the hands, unpleasant taste, skin rash, abdominal pain, urinary frequency, tremor, inj site inflammation. Rarely, diabetogenic effect.

Overdose Effects

Symptoms: Flushing, nausea, vomiting and dizziness.

Management: Symptomatic and supportive treatment.

Skin test should be done before initiating therapy. Heart failure; renal impairment. Pregnancy, lactation, childn.

Use in Special Populations

Renal Impairment: Dosage adjustment needed.

Pregnancy & Lactation

Pregnancy Category C. Either studies in animals have revealed adverse effects on the foetus (teratogenic or embryocidal or other) and there are no controlled studies in women or studies in women and animals are not available. Drugs should be given only if the potential benefit justifies the potential risk to the foetus.