What are the common side effects of a 5-day course of 400mg once daily albendazole (anti-parasitic medication)?

Side Effects of a Five-Day Course of 400mg Once Daily Albendazole

A five-day course of albendazole 400mg once daily typically causes minimal side effects in most patients, with gastrointestinal symptoms being the most common adverse reactions.

Common Side Effects

• Gastrointestinal symptoms are the most frequent adverse reactions:

  • Abdominal pain (reported in up to 6% of patients) 1, 2
  • Nausea (4-6% of patients) 1, 2
  • Vomiting (4-6% of patients) 1, 2

• General symptoms:

  • Headache (reported in 1-11% of patients) 1, 2
  • Dizziness/vertigo (reported in approximately 1% of patients) 1, 2
  • Fever (reported in about 1% of patients) 1

Less Common Side Effects

• Dermatological reactions:

  • Reversible alopecia (hair loss) occurs in approximately 2% of patients 1, 2
  • Rash and urticaria (hypersensitivity reactions) occur in less than 1% of patients 2

• Neurological symptoms:

  • May unmask previously undiagnosed neurocysticercosis in patients from endemic areas 2
  • Can cause exacerbation of neurological symptoms due to inflammatory reaction from parasite death 3

Serious but Rare Side Effects

• Hepatic effects:

  • Elevated liver enzymes occur in approximately 16% of patients, especially during prolonged treatment 3, 2
  • These elevations generally return to normal upon discontinuation of therapy 2
  • Rare cases of acute liver failure and hepatitis have been reported 2, 4, 5

• Hematological effects:

  • Leukopenia, granulocytopenia, pancytopenia, agranulocytosis, or thrombocytopenia have been reported in less than 1% of cases 2
  • These are more common with prolonged treatment courses rather than short 5-day regimens 3

Important Considerations

• Short courses (1-5 days) for intestinal helminth infections generally have minimal side effects compared to longer treatment courses 3

• Side effects are typically mild and transient, resolving without specific treatment 6

• Monitoring recommendations:

  • For a 5-day course, routine monitoring of liver enzymes or blood counts is not typically required in patients without pre-existing liver disease 3, 2
  • Patients with liver disease are at increased risk for bone marrow suppression and warrant more careful monitoring 2

• Pregnancy considerations:

  • Albendazole may cause fetal harm based on animal studies 2
  • Pregnancy testing is recommended for females of reproductive potential prior to therapy 2
  • Effective contraception should be used during treatment and for 3 days after the final dose 2

Clinical Pearls

• Taking albendazole with food increases absorption and efficacy 2
• The side effect profile differs depending on the indication - side effects are more common with longer treatment courses used for tissue parasites (neurocysticercosis, echinococcosis) than with short courses for intestinal helminths 3, 2
• Avoid concomitant use of dexamethasone when possible, as it increases albendazole sulfoxide concentrations by approximately 56% 2
• In cases of strongyloidiasis, caution should be used with steroids as they may precipitate hyperinfection syndrome 1, 7