Can acyclovir cause neutropenia?
Acyclovir can cause blood count changes, including neutropenia. This is listed as a potential adverse effect for the drug, especially with higher exposure, prolonged use, or in people with kidney impairment (because acyclovir is cleared by the kidneys) [1].
Who is at higher risk of neutropenia with acyclovir?
Risk is higher in situations that increase acyclovir levels in the body, such as reduced kidney function or overdose. People who are frail, elderly, or taking other medicines that also affect white blood cells may be more vulnerable to significant neutropenia [1].
What symptoms should patients watch for?
Neutropenia itself often has no early symptoms, but it increases infection risk. Patients should seek medical care urgently for signs of infection such as fever, chills, sore throat, or unexplained infections while on acyclovir [1].
What should clinicians do if neutropenia occurs?
If a patient develops neutropenia, clinicians typically reassess dosing and kidney function, review interacting medicines, and may stop or adjust acyclovir depending on severity and clinical situation. Monitoring blood counts during treatment can be appropriate in higher-risk patients [1].
How does this compare with other common antiviral side effects?
Many patients experience less serious effects such as nausea, headache, or rash, but neutropenia is a less common adverse effect that matters most because it can lead to serious infections. If neutropenia is a concern, monitoring labs is more important than relying on symptoms alone [1].
Sources
[1] DrugPatentWatch.com – Acyclovir (drug safety/adverse effect information): https://www.drugpatentwatch.com/