Acyclovir is almost completely broken down by the liver when taken orally, whereas valacyclovir has an oral bioavailability level of approximately 50 percent compared to approximately 12 percent for oral acyclovir. What is valacyclovir hydrochloride? Then, another doctor upped my dose to 400mg twice a day. Still sucks though.This stuff makes a huge difference in the duration and pain of cold sores. Using a pestle and mortar, grind 5 valacyclovir caplets for 25 mg/mL suspension or 10 valacyclovir caplets for 50 mg/mL suspension until a fine powder is produced. They would appear at the most frustrating times! Available for Android and iOS devices.Herpes Simplex, Mucocutaneous/Immunocompromised HostView side-by-side comparisons of medication uses, ratings, cost, side effects, interactions and more.View side-by-side comparisons of medication uses, ratings, cost, side effects, interactions and more.I used to get cold sores four or five times a year, sometimes more often (especially when I was dealing with the stress of college). It is known, however, that among women taking acyclovir, concentrations of acyclovir in breast milk are about four times higher than in the mother's blood. 2. 3. I didn't get a cold sore for almost five years!I became very irritated down there to the point it hurt to go to the bathroom I schedule an appointment for the doctor and they told me I had a yeast infection I then noticed bumps down there and they tested for HSV2 (herpes simplex 2) came back positive. • Valaciclovir is more bioavailable than acyclovir.• Valacyclovir is more effective when given orally than acyclovir. :( Since being on valacyclovir however, plus lysine and icing the pre-sores, my life has been a little less miserable in the cold sore department. Currently day 3 of acyclovir and I am so happy to almost be back to myself. Acyclovir is almost completely broken down by the liver when taken orally, whereas valacyclovir has an oral bioavailability level of approximately 55%. Valtrex thus is active against the same viruses as acyclovir, but Valtrex has a longer duration of action than acyclovir and can be taken fewer times each day. The half-life in adults is about 3 hours. The pain I went through was unbearable... had to call out of work several times because I could barely walk. Usually don't have any cold sores anymore. So usually the daily suppressor and emergency 1g works, but sometimes life is just too much. Because these two are in the same class, their mechanism of action is similar. It gets cleared off the body fairly quickly. If I'm really careful about avoiding the things that cause me problems, I can prevent them but it's nice to have the valacyclovir for those times when I don't get it right.The half-life of a drug is the time taken for the plasma concentration of a drug to reduce to half its original value.We comply with the HONcode standard for trustworthy health information - Valacyclovir is an antiviral drug that helps treat herpes and varicella-zoster infections. There may be variations in CSA schedules between individual states.Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.The easiest way to lookup drug information, identify pills, check interactions and set up your own personal medication records. 4. Therefore to obtain high concentrations, acyclovir should be given intravenous. We will see how this medicine works for me overtimeI take valacyclovir 500mg once a day. Acyclovir and Valaciclovir are two antiviral drugs.