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The information provided is taken from various reference sources. It is provided as a guideline. No responsibility can be taken by the author or the Breastfeeding Network for the way in which the information is used. Clinical decisions remain the responsibility of medical and breastfeeding practitioners. The data presented here is intended to provide some immediate information but cannot replace input from professionals.
Aciclovir can be taken by a breastfeeding mother with shingles together with paracetamol and a non-steroidal drug e.g. ibuprofen
Shingles, also known as herpes zoster, is a painful skin rash caused by the reactivation of the chickenpox virus (varicella-zoster virus) in people who have previously had chickenpox. Early symptoms can include a headache, burning, tingling, numbness or itchiness of the skin in the affected area (normally the area is in a line often across the tummy, back or face), a feeling of being generally unwell accompanied by a temperature.
Many mothers with shingles will be prescribed a course of antiviral tablets lasting seven days, usually acyclovir 800mg.
Commonly prescribed antiviral medicines include aciclovir, famciclovir and valaciclovir. These medications can’t kill the shingles virus, but can help stop the virus multiplying reducing the severity of the symptoms and lowering the risk of post-herpatic neuralgia which can last several months. Medicines are most effective when taken within 72 hours of symptoms so it is important to consult a healthcare professional quickly. You may also need to take painkilling medication such as paracetamol and ibuprofen (see factsheet on analgesics and breastfeeding).
If the rash is only on your body and can be covered by clothing, there’s little risk of passing the infection on to others even before the lesions have dried.
Aciclovir (Zovirax ®) can be given during lactation as it achieves less than 1% of the paediatric licensed dose. Oral bio-availability of aciclovir is limited. It is widely used to treat neonates and its safety is well established Lau 1987, Frenkel 1991,Meter 1988, Taddio 1994)
Famciclovir (Famvir ®) has greater bio-availability than aciclovir but data is not available on its transfer into breastmilk. It has no particular benefits over aciclovir and is more expensive so unless there are compelling reasons why this drug should be used, aciclovir would be preferred during lactation. It is not used in children.
Valacyclovir (Valtrex®) is a prodrug that is rapidly converted to acyclovir in the body.
- Lau RJ, Emery MG, Galinsky RE, Unexpected accumulation of acyclovir in breastmilk with estimation of infant exposure, Obstet Gynecol, 1987;69:468–71.
- Frenkel LM, Brown ZA, Bryson YJ, Corey L, Unadkat JD, Hensleigh PA, Arvin AM, Prober CG, Connor JD, Pharmacokinetics of acyclovir in the term human pregnancy and neonate, Am J Obstet Gynecol, 1991;164:569–76.
- Meyer LJ, de Miranda P, Sheth N, Spruance S, Acyclovir in human breastmilk, Am J Obstet Gynecol, 1988;158:586–8.
- Taddio A, Klein J, Koren G, Acyclovir excretion in human breastmilk, Ann Pharmacother, 1994;28:585–7
- Jones W Breastfeeding and Medication Routledge 2018
- Hale T Medications and Mothers Milk
- LACTMED online access
©Dr Wendy Jones MBE, MRPharmS and the Breastfeeding Network Sept 2019