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Name of the generic: valacyclovir [val-a-sye kloe-veer]
The brand name is Valtrex.
Drug class: purine nucleosides

What is Valacyclovir?

Valacyclovir is an antiviral medication. It reduces the expansion and spread of the herpes virus, helping your body fight infection.Valacyclovir can be used to combat infections caused by herpesviruses, including herpes genital, cold sores, and shingles (herpes zoster) in adults.

Valacyclovir helps treat sores caused by the cold that occur in children that are 12 years old, as well as chickenpox in children aged at least two years old.Valacyclovir is not a cure for herpes, and it will not stop you from passing the virus on to others. However, it can reduce the symptoms associated with an infection.


Before taking valacyclovir, tell your doctor that you suffer from HIV/AIDS, an insufficient immune system, kidney disease (or, in the case of dialysis), or have received an organ transplant or bone marrow transplant.

Valacyclovir may be harmful to the kidneys. The effects can be exacerbated when used in conjunction with other medications that may cause harm to the kidneys.Inform your physician of all medications you are currently taking. There may be a need for dose adjustments or tests if you are taking certain medicines in conjunction with valacyclovir.

Treatment with valacyclovir needs to be initiated as soon as possible, following the initial signs of symptoms (such as burning, tingling blisters, etc.).Valacyclovir is not able to stop the transmission of herpes genitalis. Herpes infections are infectious and can cause infections in other people while you're taking this medication.

Stop taking valacyclovir and consult your doctor immediately in case you notice any indications of serious side effects that may affect red blood cells, like symptoms like the appearance of bruising, swelling, or bleeding or red spots on the skin (not connected to chickenpox or herpes). Bloody diarrhea, vomiting, yellow or pale skin weakening, fainting or urinating less frequently than normal, or none at all.

Similar/related drugs

Prednisone, Acyclovir, Valtrex, Zovirax, Deltasone, Topical Tetracaine, and Lysine

Before you take this drug

This medicine is for you if you're allergic to acyclovir or valacyclovir (Zovirax).

To ensure that valacyclovir is appropriate for you, consult your doctor if you suffer from:

  • Kidney disease (or if you're taking dialysis)
  • HIV/AIDS or other diseases that can affect the immune system
  • An underlying background of kidney transplantation or bone marrow transplant

It isn't known if this medication will cause harm to the unborn baby. The herpes virus may be passed from an affected mother to her infant in the course of childbirth. If you are suffering from genital herpes, it is crucial to avoid herpes-related lesions in your pregnancy in order to not develop genital lesions at the time your baby is born.

Valacyclovir is a drug that can be absorbed into the breastmilk of a baby and could harm a nursing child. Consult your physician if you are breastfeeding the baby.Don't give Valacyclovir to children under the age of 18 without medical guidance.

How to take Valacyclovir?

Use valacyclovir exactly as it was prescribed to you. Follow the instructions on the prescription label. Do not take this medication in greater or lesser doses or for longer than prescribed.Begin taking valacyclovir as quickly as you can after the initial manifestation or symptom (such as burning, tingling, blisters, etc.). The medicine may prove less effective when it is first started just one or two days after the onset of symptoms.

Some herpes-related infections require treatment for a longer period than other herpes infections. Use this medicine for the entire prescribed duration. The symptoms could improve before the infection is completely gone. The absence of doses can increase the chance of the virus developing resistance to antiviral drugs.You can take valacyclovir either in combination with food or not.

Consult your physician if a child who is taking this medicine has difficulty swallowing the tablet of valacyclovir.Drink plenty of fluids while you are taking valacyclovir in order to keep your kidneys functioning effectively.

Herpes virus-related lesions are best kept as tidy and dry as possible. Wearing loose clothes can assist in avoiding irritation to the lesions.Place tablets in a cool, dry place at room temperature, away from heat and moisture.

What happens if I miss the dose?

You should take the missed dose as soon as you can remember. Do not take any missed doses if you are nearing the time for the next dose.Do not attempt to compensate for missed doses with additional medication.

What happens if I overdose?

For medical emergencies, seek emergency medical attention or contact the Poison Help Line toll-free at 1-800-222-1222.

What should be avoided?

This medication won't hinder you from transmitting herpes genitals to other people. Herpes infections can be contagious and can spread to others, even when you're taking valacyclovir.

Beware of sexual contact or use a condom made of latex to stop you from transmitting the virus to other people. Be careful not to let infected areas come into contact with others. Avoid touching the infected area; after that, avoid touching your eyes. Make sure to wash your hands regularly to avoid spreading the infection.Don't share valacyclovir with someone else, even if they suffer from the same symptoms as you do.

Side effects of Valacyclovir

Contact a medical professional immediately. If you are experiencing symptoms of an allergic reaction to the medication valacyclovir, such as hives, difficulty breathing, and swelling of your lips, face, and tongue,

Contact your doctor immediately. If you suffer from:

  • Anger, confusion, or you feel unsteady or unstable
  • Hallucinations (seeing and hearing sounds that aren't real);
  • Issues with speech problems;
  • A seizure (convulsions);
  • Kidney problems: no or little urine; pain or difficulty with urine; swelling of your ankles or feet; being fatigued or feeling sluggish.

Take valacyclovir off your list and consult your physician immediately in case you experience any of these signs of an adverse reaction that may cause harm to red blood cells:

  • Fever, pale skin;
  • Unusual bleeding (nosebleeds, bleeding gums);
  • Urine that is pink or red with little or no urination
  • Red spots on the skin (not connected to chickenpox or herpes);
  • Fatigue or feeling weak;
  • Stomach pain, bloody diarrhea, vomiting,
  • Swelling on your hands, face, or feet.

Some side effects are more common in those who are 65 years old or older.

Common side effects of valacyclovir include:

  • Nausea, stomach pain,

This isn't an exhaustive list of possible side effects, and other side effects could be present. Consult your physician for advice regarding medical adverse effects. You can report any side effects to the FDA at 1-800-FDA-1088.

Interaction with other drugs

Valacyclovir is known to harm the kidneys. This is especially true if you take other medications, like chemotherapy, antivirals, injectable antibiotics, medications for bowel issues, medicines that treat high blood pressure, medications to stop rejection of organ transplants, injection-able osteoporosis medications, as well as some arthritis or pain medications (including Advil, Motrin, and Aleve).

Other medications may be incompatible with valacyclovir, such as medications that are prescribed and available over the counter, as well as vitamins and herbal products. Inform your health professionals about the medicines you take currently and all medicines that you decide to stop or begin taking.



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