Salmon calcitonin is commercially available as an injectable formulation and as a nasal spray. This 32-amino-acid peptide secreted by the C-cells of the thyroid inhibits activity of osteoclasts, slows bone resorption, but induces only a mild increase in bone mineral density BMD [1].

Nasal salmon calcitonin decreased the incidence of vertebral fractures by 33 % in older osteoporotic women, most of whom had prevalent vertebral fractures [2].

The anti-fracture effect was observed after at least 3 years of treatment and only for the dose of 200 I.U. daily, but not for those of 100 and 400 I.U. daily.

There is no evidence for efficacy of nasal salmon calcitonin on non-vertebral fractures.

In men with idiopathic osteoporosis, nasal salmon calcitonin reduces bone turnover and increases lumbar spine BMD [3].

Of interest, salmon calcitonin appears to reduce the pain associated with acute vertebral fractures [4].

Salmon calcitonin is safe apart from very rare allergic reactions. However, due to its limited anti-fracture efficacy relative to other available agents, nasal salmon calcitonin is not considered a first-line therapy.

References

1. Chesnut CH 3rd, Azria M, Silverman S, Engelhardt M, Olson M, Mindeholm L 2008 Salmon calcitonin: a review of current and future therapeutic indications. Osteoporos Int 19:479-491.
2. Chesnut CH 3rd, Silverman S, Andriano K, Genant H, Gimona A, Harris S, Kiel D, LeBoff M, Maricic M, Miller P, Moniz C, Peacock M, Richardson P, Watts N, Baylink D 2000 A randomized trial of nasal spray salmon calcitonin in postmenopausal women with established osteoporosis: the prevent recurrence of osteoporotic fractures study. PROOF Study Group. Am J Med 109:267-276
3. Trovas GP, Lyritis GP, Galanos A, Raptou P, Constantelou E 2002 A randomized trial of nasal spray salmon calcitonin in men with idiopathic osteoporosis: effects on bone mineral density and bone markers. J Bone Miner Res 17:521-527.
4. Blau LA, Hoehns JD 2003 Analgesic efficacy of calcitonin for vertebral fracture pain. Ann Pharmacother 37:564-570