Calcitonin
Calcitonin, a peptide. 32-residue peptide from thyroid C-cells. Activates calcitonin receptors on osteoclasts → inhibits bone resorption… Subcutaneous half-life 1.5 h.
32-residue peptide from thyroid C-cells. Activates calcitonin receptors on osteoclasts → inhibits bone resorption and lowers serum Ca²⁺. Salmon calcitonin is 40× more potent than human form and is the standard pharmaceutical. Modest osteoporosis benefit vs bisphosphonates; main clinical niche is acute hypercalcemia of malignancy (fast onset, short duration).
PK is SALMON calcitonin (the marketed peptide), verbatim from Beveridge 1976 (PMID:64046), 18 patients: "the elimination half-lives 1 and 1.5 hours" (IM, SC), "The volume of distribution was 11 litres" and "The bioavailability of the intramuscular and subcutaneous forms was found to be 66 and 71% respectively". All three stored values are supported as stored. mw_g_mol 3431.9 is salmon calcitonin (PubChem CID 16220016); human calcitonin is a different peptide at 3417.9 and is not interchangeable. Note the 11 L volume was measured on the IV arm.
Pharmacokinetics
- Subcutaneous — t½ 1.5 h · F 71% · Vd 11 L
Sources: PMID:64046