• Acyclovir belongs to the family of medicines called antivirals. It slows the growth and spread of the herpes virus, it is used to treat the symptoms of chickenpox, shingles, herpes virus infections of the genitals, skin, and mucous membranes.

How should you take this medication?

• Acyclovir can be taken with or without food. Taking acyclovir with food may decrease stomach upset. Drink plenty of liquids while receiving Acyclovir.
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  If you are using acyclovir oral suspension, shake the oral suspension well just before you measure a dose. To be sure you get the correct dose, measure the liquid with a marked measuring spoon or medicine cup, not with a regular table spoon.
   
• Drink plenty of liquids while receiving Acyclovir.
   
• If you do miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

General Precautions with Acyclovir

• Do not take this medicine if you are allergic to acyclovir or valacyclovir. Before taking acyclovir, tell your doctor if you are allergic to any drugs, or if you have kidney disease.
   
• Acyclovir may cause drowsiness, dizziness, or changes in vision. Do not drive, operate machinery, or do anything else that could be dangerous until you know how you react to Acyclovir.
   
• Acyclovir may cause increased sensitivity to the sun. Avoid exposure to the sun, sunlamps, or tanning booths until you know how you react to this medicine.
   
• Acyclovir is not expected to be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

What are the possible side effects of Acyclovir?

• Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
   
• Check with your doctor if any of these common side effects persist or become bothersome: diarrhea, dizziness, drowsiness, nausea, vomiting, sensitivity to sunlight.