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Updated: Jun 25, 2026
06:41
A New Technique for Quantitative Analysis of Hair Loss in Mice Using Grayscale Analysis
Published on: March 9, 2015
Chloroquine -induced hair depigmentation.
T B Di Giacomo1, N Y S Valente, M M S Nico
1Department of Dermatology, Hospital das Clínicas, University of Sao Paulo, Sao Paulo, Brazil. thabello@hotmail.com
Lupus
|February 14, 2009
Summary
Chloroquine diphosphate overdosage caused temporary hair depigmentation in an 11-year-old patient. Normal hair color returned after the patient
Area of Science:
- Dermatology
- Pharmacology
- Pediatrics
Background:
- Dermatomyositis is an autoimmune disease affecting skin and muscles.
- Chloroquine diphosphate is a medication used to treat various conditions, including autoimmune diseases.
- Drug-induced side effects can manifest in various ways, including changes in hair pigmentation.
Observation:
- An 11-year-old patient diagnosed with dermatomyositis experienced hair depigmentation.
- The hair depigmentation was associated with a subacute overdosage of chloroquine diphosphate.
- Hair color normalized after the chloroquine diphosphate dosage was adjusted to normal levels.
Findings:
- Subacute overdosage of chloroquine diphosphate can induce reversible hair depigmentation.
- The mechanism may involve interference with melanin synthesis or melanosome transfer.
- This case highlights a rare but notable side effect of chloroquine diphosphate therapy.
Implications:
- Clinicians should be aware of potential hair color changes as a side effect of chloroquine diphosphate.
- Monitoring hair pigmentation in patients receiving chloroquine diphosphate is recommended.
- Further research into the pathomechanisms of drug-induced hair depigmentation is warranted.
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