Before taking valacyclovir, tell your doctor if you have HIV/AIDS, a weak immune system, kidney disease (or if you are on dialysis), or if you have had a kidney or bone marrow transplant.
Valacyclovir can be harmful to the kidneys, and these effects are increased when it is used together with other medicines that can harm the kidneys. Tell your doctor about all other medications you are using. You may need dose adjustments or special tests when taking certain medications together with valacyclovir.
Treatment with valacyclovir should be started as soon as possible after the first appearance of symptoms (such as tingling, burning, blisters).
Herpes virus can be passed from an infected mother to her baby during childbirth. If you have genital herpes, it is very important to prevent herpes lesions during your pregnancy so that you do not have a genital lesion when your baby is born.
Valacyclovir will not prevent the spread of genital herpes. Herpes infections are contagious and you can infect other people even while you are taking with valacyclovir.
Stop taking valacyclovir and call your doctor right away if you have any signs of a serious side effect that can harm red blood cells, such as: fever, easy bruising or bleeding, red spots on the skin (not related to herpes or chickenpox), bloody diarrhea, vomiting, pale or yellowed skin, weakness, fainting, or urinating less than usual or not at all.
Do not give valacyclovir to a child unless it has been prescribed by a doctor.