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Generic Name: Valacyclovir Valacyclovir val-a-SYE kloe-veer [val-a-SYE kloe-veer
Drug class: purine nucleosides

What is Valtrex?

Valtrex is an antiviral medication. It reduces the development and spread of the herpes virus, helping the body fight off the infection.Valtrex is a medication used to combat infections caused by the herpes virus, such as herpes genital, cold sores, and herpes zoster (herpes zoster) in adults.Valtrex can be used for treating cold sores that occur in children aged between 12 and 18 years old, as well as chickenpox in children aged at least 2 years old.

Valtrex 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 of a herpes infection.Valtrex could be used for other purposes that aren't covered in this guide.


Before you take Valtrex, consult your physician to see if you suffer from HIV/AIDS, a weak immune system, kidney disease (or, in the case of dialysis), or have received a bone marrow or kidney transplant.

Valtrex is detrimental to kidneys, and these negative effects are heightened when it is combined with other medications that could affect kidneys. Discuss with your doctor all the other medications you're taking. There may be a need for dose adjustments or special tests when you take certain medications in conjunction with Valtrex.The treatment with Valtrex should be started as quickly as possible, following the initial signs of symptoms (such as burning, tingling, or blisters).

Stop taking Valtrex immediately and consult your doctor immediately when you experience any sign of a serious side effect that may affect red blood cells, for example, symptoms like the appearance of bruising, easily bruising or bleeding, and red spots on your skin (not connected to chickenpox or herpes). Bloody diarrhea, vomiting, yellow or pale skin or body, weakness, fainting or having less urination than normal, or none at all.

Before you take this drug

It is recommended not to take Valtrex in the event that you are allergic to acyclovir and valacyclovir (Zovirax).

To be sure Valtrex is appropriate for you, speak to your doctor if you are suffering from:

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

Although Valtrex usage in pregnant women is very limited, there's no evidence of a significant risk to the human fetus from Valacyclovir. The herpes virus may be passed on from an affected mother to her baby during birth. If you are suffering from the genital herpes virus, it is vital to keep your eyes open for herpes lesions throughout your pregnancy to ensure that you don't develop a genital blemish 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.Notify your doctor immediately if you plan on breastfeeding the baby.Avoid giving this medication to children without a medical consultation.

How to take Valtrex?

Use Valtrex exactly as recommended for you. Follow all the instructions on the prescription label. Don't take this medication in smaller or larger doses or for longer than prescribed.Begin taking Valtrex immediately following the first onset of symptoms (such as burning, tingling, blisters, etc.). The medicine may prove less effective when you first start taking it just one or two days after the beginning of your symptoms.

Some herpes-related infections require treatment for a longer period than other herpes infections. Use this medicine for the entire prescribed duration. Your symptoms may get better prior to the infection being completely eliminated. The absence of doses can increase the chance of the virus developing resistance to antiviral drugs.

You can take Valtrex without or with food.Inform your doctor. The child's doctor if the medicine is unable to swallow the tablet.Drink plenty of fluids while you take Valtrex to ensure your kidneys are functioning correctly.Lesions caused by the herpes virus must be treated as cleanly and dryly as possible. Wearing loose clothes can aid in preventing irritation to the lesions.Keep Valtrex tablets in a cool, dry place away from heat and moisture.

What happens if I miss the dose?

Do the dose you missed as quickly as you can remember. Avoid any missed doses if you are nearing the time for the next dose. Don't take any extra medication to make up for the missed dose.

What happens if I overdose?

Get medical attention in an emergency or contact the Poison Help Line toll-free at 1-800-222-1222.

Interaction with other drug

The use of this medication will not stop you from spreading the genital herpes virus to others. Herpes infections can be contagious, and you could infect others, even when you're taking Valtrex.

Do not engage in sexual relations or use a condom made of latex to prevent transmitting the virus to other people. Do not let the infected area be touched by others. Avoid touching the infected area; after that, avoid touching your eyes. Make sure to wash your hands regularly to stop the spread of infection.Don't share this medication with someone else, even if they suffer from similar symptoms to yours.

Side effects of Valtrex

Contact a medical professional immediately. If you are experiencing symptoms of an allergic reaction, Valtrex symptoms include difficulty breathing, hives, or swelling of your lips, face, and throat.

See your doctor right away. If you suffer from:

  • Anger, confusion, or a feeling of being shaken or unstable
  • Hallucinations (seeing things or hearing them that aren't real);
  • Issues with speech problems;
  • A seizure (convulsions);
  • Kidney problems: no or little urine, pain or difficulty urinating, swelling in your ankles and feet, and feeling exhausted or sluggish.

Do not take Valtrex, and contact your doctor immediately if you notice any of these signs of an adverse reaction that could affect red blood cells.

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

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

Common Valtrex side effects can include:

  • Nausea, stomach pain,

This is not a comprehensive list of all side effects. Other side effects could be present. Contact your doctor to seek medical advice on the effects. You can report any adverse reactions to the FDA at 1-800-FDA-1088.

Interaction with other drug

Valtrex may cause kidney damage. The risk increases if you are also taking other medications, such as chemotherapy, antivirals, antibiotics, medications for bowel problems, medications that treat high blood pressure, medications to avoid rejection of organ transplants, injection-able osteoporosis medications, as well as a few arthritis and pain medicines (including Advil, Motrin, and Aleve). Talk to your doctor if you think you're using other medicines that could affect your kidneys.

Other medications can interfere with valacyclovir. This includes medications that are prescribed and available over the counter, as well as vitamins and herbal products. Be sure to inform your health professionals about any medication you are taking in the present and about any medication that you decide to stop or begin taking.



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