Precautions and Warnings With Famciclovir
There are numerous precautions and warnings with famciclovir to be aware of before you take the medicine. For example, famciclovir can potentially interact with certain other drugs. Also, it is important to start taking famciclovir at the first signs of a cold sore, genital herpes, or shingles. Among the people who should avoid the drug are those with galactose intolerance or very severe lactose intolerance. Talk with your healthcare provider about any famciclovir precautions and warnings that may apply to you.
- Kidney disease, including kidney failure (renal failure)
- Very severe lactose intolerance
- Galactose intolerance
- Any allergies, including allergies to food, dyes, or preservatives.
Also let your healthcare provider know if you are:
- Pregnant or thinking of becoming pregnant
You should also make sure to tell your healthcare provider about all other medicines you are currently taking, including prescription and non-prescription medicines, vitamins, and herbal supplements.
Some warnings and precautions to be aware of prior to taking famciclovir include:
- The kidneys help remove famciclovir from the body. If you have kidney disease, your healthcare provider should recommend a lower famciclovir dosage for you.
- Famciclovir will not cure genital herpes. You should avoid sexual contact while having an outbreak (or if you think you are about to have an outbreak). You should always use condoms, as genital herpes can be spread at any time.
- Famciclovir should be started as soon as possible after the first signs of shingles, genital herpes, or cold sores, as it is most effective when taken early in the course of the infection.
- Famciclovir is not approved for treating herpes infection of the eye, herpes infections that have spread throughout the body, or the first genital herpes infection a person experiences (although it is approved for subsequent outbreaks). Also, it is not approved to treat shingles in people with HIV or other immune system problems.
- Famciclovir tablets contain lactose and should not be taken by people with galactose intolerance or very severe lactose intolerance.
- Famciclovir is considered a pregnancy Category B medication. This means that it is probably safe for use during pregnancy. Talk with your healthcare provider about the risks and benefits of using the drug during pregnancy (see Famvir and Pregnancy).
- It is not known if famciclovir passes through breast milk. Therefore, if you are breastfeeding or plan to start breastfeeding, discuss this with your healthcare provider prior to taking the drug (see Famvir and Breastfeeding).
- Famciclovir can interact with a few other medications (see Drug Interactions With Famciclovir).