The calcium channel blocker amlodipine besylate was effective in reducing the number of muscle cramps caused by vismodegib, a basal cell carcinoma drug, according to a research letter from Dr. Mina Ally and her associates.
Patients who took amlodipine had the number of muscle cramps halved after 2 weeks of treatment, and this level was maintained for the 8-week medication regimen. No significant change in cramp severity, duration, or frequency of nighttime awakenings was seen. Side effects only appeared in too patients, with one reporting mild intermittent dizziness and another reporting grade 1 peripheral edema.
The control group saw a nonsignificant increase in cramp frequency, compared with the significant decrease in the amlodipine group. No change was seen in cramp severity, duration, or number of nighttime awakenings in the control group.
“Amlodipine may be effective in vismodegib-induced muscle cramps because it blocks voltage-gated calcium channels and inhibits the transport of extracellular calcium into muscle that is required for contraction,” the investigators noted.
Find the full research letter in JAMA Dermatology (doi:10.1001/jamadermatol.2015.1937).