Annotation of HCSC Label for dapsone and CYB5R3
PharmGKB ID
Summary
The product monograph for dapsone gel (ACZONE) states that dapsone should be avoided in patients with congenital methemoglobinemia, which is associated with variants in CYB5R3.
Prescribing
Cases of methemoglobinemia, with resultant hospitalization, have been reported post marketing in association with twice daily dapsone gel, 5%, treatment. [...] Avoid use of ACZONE Gel, 5%, in those patients with congenital or idiopathic methemoglobinemia.
Annotation
Excerpt from the dapsone (ACZONE) product monograph:
Cases of methemoglobinemia, with resultant hospitalization, have been reported post marketing in association with twice daily dapsone gel, 5%, treatment. Patients with glucose-6-phosphate dehydrogenase deficiency, or with congenital or idiopathic methemoglobinemia, are more susceptible to drug-induced methemoglobinemia. Avoid use of ACZONE Gel, 5%, in those patients with congenital or idiopathic methemoglobinemia.
NOTE: While the CYB5R3 gene is not explicitly stated in the drug label, variants in this gene are associated with congenital methemoglobinemia I and II OMIM 250800.
For the complete product monograph text with sections containing pharmacogenetic information highlighted, see the dapsone product monograph.
*Disclaimer: The contents of this page have not been endorsed by HCSC and are the sole responsibility of PharmGKB.
Evidence for Clinical Annotations
This annotation has been used as evidence for the following clinical annotations.
History
No history available.