Drug Uses
It is utilized for treating shingles (herpes zoster). It is also used for treating or suppressing herpes in individuals, who are immune competent. Individual infected with HIV also use it to suppress recurring genital herpes. It can even be used for treating herpes labialis (cold sores).

Drug Precautions
If you have an allergy to Zovirax (acyclovir), take the medication only after consultation from your physician. Prior to taking it, you should confirm your doctor for any disease in your kidney or problem with your immune system. In those cases, you might be served with adjustment in dosage or extra attention during your treatment.
Valtrex belongs to the Category B of FDA pregnancy. This category has a host of drugs that are not harmful for unborn babies. However, you should always consult your physician in case you are expecting or having a baby prior to taking the medication.
There is still no information of the effects of Valtrex on breast milk, i.e. its eventual effect on your nursing baby. Still, you should confirm with your doctor in case you have to breast-feed your baby.

Drug Interactions
Valtrex interactions with different medications, that include probenecid, tenofovir and cimetidine, can enhance the Valtrex level in blood. There are cases where such increased levels are harmless for patient and no adjustment is required in the dosage. However if your kidney is functioning poorly, there are risks of major side effects on your body systems. In these cases, healthcare providers adjust the doses for your benefits.

Side Effects
There are certain side effects that are seen with Valtrex. Most common amongst them is problem in gastrointestinal system that causes vomiting, nausea, constipation, abdominal pain or diarrhea. There are also possibilities of you shaking (having tremors), feeling dizziness or having headaches. In case you find any of these effects bothering you or other things that has cropped up after the medication, you should consult your doctor immediately.

Missed Dose
In case for any given reason you have missed a Valtrex dose, you can take whenever you remember it and follow it up with your regular schedule. However in case it is time for the next dose and then you remember the missed dose, you should avoid it. Action in such cases might lead to overdose and further side effects.

Overdose
In case you suspect any of the overdose symptom involved in your body, you should opt for immediate medical attention from your physicians. Although exact overdose symptoms of Valtrex are unknown, you can contact your physician if you notice any overdose symptoms that are common with acyclovir.
In acyclovir, you might face hallucinations, kidney damages (decrease in the production of urine) and seizures.

Storage
You should store this medication at about 15°C - 25°C. Again, it should be stored in a place where younger family members cannot reach. You should avoid storing the drug if it has passed its expiry.