Encyclopedia · drug with hair side effects
Hedgehog pathway inhibitors (vismodegib, sonidegib)
Skin-cancer pills that block the Hedgehog pathway, which drives follicle growth, caused hair loss in 56.9% of patients in a meta-analysis, the highest of any targeted cancer drug.
What it is
Vismodegib and sonidegib are prescription oral drugs for advanced basal cell carcinoma.
How it works
Hedgehog signalling is needed for the follicle's growth phase. Blocking the smoothened receptor pushes hairs out of cycle.
What the studies show
- A meta-analysis of trials of targeted cancer drugs found an overall all-grade alopecia rate of 14.7%. Vismodegib was highest at 56.9% (95% CI 50.5-63.1) and bortezomib lowest at 2.2%. Belum 2015
- Whether the hair loss regrows after stopping was not established in the sources we read.
How it's used in studies
Not applicable; this is adverse-effect data.
Side effects and safety
Hair loss is one of several common effects. We did not verify other safety details on this page, so check the current label.
Bottom line
Anyone starting these drugs should expect hair thinning. Discuss with a doctor.
Fun facts
- More than half of patients on vismodegib lost hair, the highest rate among the targeted cancer therapies in one meta-analysis, because the pathway they block is the one follicles use to grow. Belum 2015
Studies 1
Belum VR et al. Alopecia in patients treated with molecularly targeted anticancer therapies. Ann Oncol. 2015
Result: Overall all-grade alopecia 14.7% (RR 7.9 vs placebo); vismodegib 56.9% (95% CI 50.5-63.1); bortezomib lowest at 2.2%.
Read the study ↗Related
- EGFR inhibitors (erlotinib, cetuximab)Cancer drugs that block the EGF receptor can make eyelashes grow abnormally long and curly, and scalp hair curly or brittle, all reversing after the drug stops.
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- ImatinibA leukaemia drug that blocks the receptor pigment cells depend on can lighten or whiten hair reversibly, and oddly has also been listed among drugs that darkened gray hair.
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