Analgesic Effect of Salmon Calcitonin Suppositories in Patients with Acute Pain Due to Recent Osteoporotic Vertebral Crush Fractures: A Prospective Double-Blind, Randomized, Placebo-Controlled Clinical Study

Objective: To evaluate the analgesic efficacy of calcitonin suppositories (200 IU) in comparison with bed rest and paracetamol tablets, as a rescue analgesic. Design: A prospective, double-blind, randomized, placebo-controlled, clinical trial. Patients: Forty patients (8 men and 32 postmenopausal women), who had recently (within the last 5 days) suffered a nontraumatic osteoporotic vertebral fracture. Setting and Interventions: All patients were admitted to the hospital, divided randomly into two groups and received either one calcitonin or placebo suppository once a day, respectively, for 28 days. All patients were allowed to take paracetamol tablets (500 mg), with a maximum dose of six tablets daily. Outcome Measures: Spinal pain evaluation was performed at the beginning of the study (before the initiation of treatment) and then daily until the end of the study (day 28) using the Huskinsson's visual analog scale (VAS) and a painmeter device, by direct pressure on the fractured vertebra. Pain was evaluated with the patients attempting or performing four different locomotor functions, e.g., bed rest, sitting, standing, and walking functions. Biochemical urine and plasma measurements were carried out before the initiation of treatment and on days 14 and 28. Results: All calcitonin-treated patients experienced an overall statistically significant (all p values < 0.001) decrease of spinal pain as assessed by the VAS and the painmeter device. Pain relief allowed for early mobilization and the gradual restoration of the locomotive functions in the calcitonin-treated group. Placebo-treated patients remained in bed for almost the whole of the observation period. At the end of the study (28th day), fasting osteocalcin, hydroxyproline/creatinine, and calcium/creatinine ratio values were statistically significantly (all p values < 0.001), lower in the calcitonin-treated than in the placebo-treated patients. In the placebo group these values showed a gradual increase. In the calcitonin-treated group side effects mainly included dizziness and enteric irritation caused by the suppositories. Enteric irritation was also present in the placebo-treated group. Conclusions: Salmon calcitonin suppositories (200 IU daily) caused a dramatic decrease in spinal pain in patients with recent osteoporotic vertebral fractures and influenced the early mobilization and the gradual restoration of their locomotor functions.