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5-fluorouracil, 5-FU
Adrucil, Efudex, Fluoroplex

Pregnancy Category D

Drug classes


Mechanism of action

Inhibits thymidylate synthetase, leading to inhibition of DNA synthesis and cell death.


  1. Palliative management of carcinoma of the colon, rectum, breast, stomach, pancreas in selected patients considered incurable by surgery or other means (parenteral)
  2. Topical treatment of multiple actinic or solar keratoses
  3. Topical treatment of superficial basal cell carcinoma

Unlabeled use: topical treatment of condylomata acuminata
Orphan drug uses: in combination with interferon alpha 2-a recombinant for esophageal and advanced colorectal carcinoma; with leucovorin for colon/rectum metastatic adenocarcinoma Use caution in the presence of bone marrow suppression, radiation therapy.


  1. Allergy to fluorouracil
  2. Poor nutritional status
  3. Serious infections
  4. Hematopoietic depression secondary to radiation or chemotherapy
  5. Impaired liver function
  6. Pregnancy
  7. Lactation

Adverse effects 

  • CNS: Lethargy, malaise, weakness, euphoria, acute cerebellar syndrome, photophobia, lacrimation, decreased vision, nystagmus, diplopia
  • GI: Diarrhea, anorexia, nausea, vomiting, cramps, enteritis, duodenal ulcer, duodenitis, gastritis, glossitis, stomatitis, pharyngitis, esophagopharyngitis
  • CV: Myocardial ischemia, angina
  • Hematologic: Leukopenia, thrombocytopenia, elevations in alkaline phosphatase, serum transaminase, serum bilirubin, lactic dehydrogenase
  • Dermatologic: Alopecia, dermatitis, maculopapular rash, photosensitivity, nail changes including nail loss, dry skin, fissures
  • Other: Fever, epistaxis


  • Hematologic: Leukocytosis, thrombocytopenia, toxic granulation, eosinophilia
  • Local: Local pain, pruritus, hyperpigmentation, irritation, inflammation and burning at the site of application, allergic contact dermatitis, scarring, soreness, tenderness, suppuration, scaling and swelling

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