What Is It
This medication is an antiviral agent used in the treatment of herpes zoster (shingles), genital herpes and is also being used for herpes simplex (cold sores). 

How To Use
Take usually 1 tablet 2 times daily for acute outbreaks and 1 tablet daily as a maintenance dose if needed. Take Valtrex by mouth as directed. Do not skip doses or stop taking this without your doctor's approval. Stopping therapy too soon may result in ineffective treatment. 

Storage
Store this medication at room temperature between 59 and 77 degrees F (15 to 25 degrees C) away from heat and light. Keep this and all medications out of the reach of children.

Missed Dose
Try to take each dose at the scheduled time. If you miss a dose, take it as soon as remembered; do not take it if it is near the time for the next dose, instead, skip the missed dose and resume your usual dosing schedule. Do not "double-up" the dose to catch up. 

Side Effects
Nausea, vomiting, headache, loss of appetite, weakness, stomach pain or dizziness may occur the first several days as your body adjusts to the medication. If any of these effects continue or become bothersome, inform your doctor. Notify your doctor if your condition does not appear to improve or you experience a worsening of symptoms while taking Valtrex. 

Precautions
Tell your doctor if you have any kidney disease, blood disorders or if you have any allergies. This medication should be used only if clearly needed during pregnancy. Discuss the risks and benefits with your doctor. It is not known if this medication appears in breast milk. Consult with your doctor before breast-feeding. 

Drug Interactions
Tell your doctor of any over-the-counter or prescription medication you may take including cimetidine or probenecid. 
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