About & Methodology
How this resource is built, classified, and maintained.
Last reviewed: May 2026 (next review: May 2027) • Sources include CPIC pharmacogenetic guidelines, NIH/MedlinePlus, WHO, AAP, NCBI Bookshelf, and peer-reviewed literature.
This resource is educational and does not replace care from a licensed clinician or pharmacist.
What this is
The G6PD Safety Lookup is a free, ad-free educational reference for people living with glucose-6-phosphate dehydrogenase (G6PD) deficiency and their families. It summarizes published evidence about medications, foods, herbs, supplements, and treatments that have been associated with hemolysis in G6PD-deficient individuals, along with items that are commonly listed online but lack strong supporting evidence.
It is not a diagnostic tool. It does not replace evaluation by a licensed clinician or pharmacist, and it cannot account for every individual factor (G6PD variant, dose, age, illness, pregnancy, co-administered medications).
How items are classified
Each item is assigned to one of four categories based on the strongest available published evidence:
- Avoid — Strong, consistent evidence of hemolysis in G6PD-deficient individuals.
- Use Caution — Real but variable risk; often dose-dependent or limited to severe (Class I) deficiency.
- Often Listed — Weak Evidence — Frequently named on internet lists, but high-quality studies do not show clear harm at normal exposures.
- Generally Considered Safe — Reasonable, evidence-based options generally considered safe when used appropriately.
Source hierarchy
When sources conflict, we weight them in roughly this order:
- CPIC pharmacogenetic guidelines and other professional society guidelines.
- Systematic reviews and meta-analyses in peer-reviewed journals.
- NEJM, Blood, Lancet, JAMA, and equivalent high-impact primary literature.
- WHO classifications and national regulatory drug labels.
- NIH MedlinePlus, AAP, NCBI Bookshelf / StatPearls summaries.
- Hospital and academic medical center patient education (e.g. Mayo, CHOP).
- Lower-tier patient-facing lists are used only to flag items for review and never to up- or down-grade a classification on their own.
See the References page for the full citation list.
Review cadence
The full database is reviewed at least annually. Current review: May 2026. Next scheduled review: May 2027. Material changes are logged in the changelog.
Conflict of interest
This site is independently maintained. It accepts no advertising, sponsorships, affiliate commissions, or payments from pharmaceutical, supplement, or device manufacturers. It does not collect personal health information.
Report an error or suggest a source
Clinicians, pharmacists, and patients are encouraged to report inaccuracies or suggest additional peer-reviewed sources.