ExoticRx · exoticrx.com/drugs/fluorouracil
US brand names:Efudex, 5-FU
Converted to active metabolites that inhibit thymidylate synthase, blocking DNA synthesis. Also incorporates into RNA, disrupting RNA processing.
LETHAL TO CATS — even topical exposure can be fatal. Severe neurotoxicity in cats. In dogs, causes myelosuppression and GI toxicity. Handle with extreme caution.
Species references:All Dog (Domestic) drugs
Each ExoticRx dose rule is graded by the strength of its primary evidence — see the editorial process.
A dog/cat sample is shown here. Cited dosing for all 1 species — reptiles, birds, pocket pets, livestock, and equine — is free on the per-species pages above. Pro adds the weight-based calculator for every species.
| Species | Route | Dose | Frequency | Evidence | Source |
|---|---|---|---|---|---|
| Dog (Domestic) | Topical | Topical only for superficial skin tumors | Apply 5% cream to lesion q12h | Moderate | Withrow & MacEwen's Small Animal Clinical Oncology, 6th Ed |
Upgrade to Pro or Student to unlock the full dose ranges and frequency for every species. The drug's mechanism, warnings, indications, and cited sources are free to read.
View PlansSource citations and evidence levels available on the live page. Reference only — verify against current literature before clinical use.