Valaciclovir, also spelled valacyclovir, is an antiviral medication used to treat outbreaks of herpes simplex or herpes zoster (shingles). It is also used to prevent cytomegalovirus following a kidney transplant in high risk cases. It is taken by mouth.Common side effects include headache and vomiting. Severe side effects may include kidney problems. Use in pregnancy appears to be safe. It is a prodrug, which works after being converted to aciclovir in a persons body.Valaciclovir was patented in 1987 and came into medical use in 1995. It is on the World Health Organizations List of Essential Medicines. It is available as a generic medication. In 2019, it was the 110th most commonly prescribed medication in the United States, with more than 5 million prescriptions. Medical uses
Valaciclovir is used for the treatment of HSV and VZV infections, including:
Oral and genital herpes simplex (treatment and prevention)
Reduction of HSV transmission from people with recurrent infection to uninfected individuals
Herpes zoster (shingles): the typical dosage for treatment of herpes is 1,000 mg orally three times a day for seven consecutive days. Prevention of cytomegalovirus following organ transplantation
Prevention of herpesviruses in immunocompromised people (such as those undergoing cancer chemotherapy)
Chickenpox in children (ages 2–18)It has shown promise as a treatment for infectious mononucleosis and is preventively administered in suspected cases of herpes B virus exposure.Bells palsy does not seem to benefit from using valaciclovir as its only treatment. Adverse effects
Common adverse drug reactions (≥1% of people) associated with valaciclovir are the same as for aciclovir, its active metabolite.
The Population Reference Intakes are higher than the US Recommended Dietary Allowances, with the exception of pregnancy. Iron malabsorption
Iron from food is absorbed into the bloodstream in the small intestine, primarily in the duodenum. Iron malabsorption is a less common cause of iron-deficiency anemia, but many gastrointestinal disorders can reduce the bodys ability to absorb iron. There are different mechanisms that may be present. In celiac disease, abnormal changes in the structure of the duodenum can decrease iron absorption. Abnormalities or surgical removal of the stomach can also lead to malabsorption by altering the acidic environment needed for iron to be converted into its absorbable form. If there is insufficient production of hydrochloric acid in the stomach, hypochlorhydria/achlorhydria can occur (often due to chronic H. pylori infections or long-term proton-pump inhibitor therapy), inhibiting the conversion of ferric iron to the absorbable ferrous iron.Bariatric surgery is associated with an increased risk of iron deficiency anemia due to malabsorption of iron. During a Roux-en-Y anastamosis, which is commonly performed for weight management and diabetes control, the stomach is made into a small pouch and this is connected directly to the small intestines further downstream (bypassing the duodenum as a site of digestion). About 17-45% of people develop iron deficiency after a Roux-en-Y gastric bypass. Pregnant women
Without iron supplementation, iron-deficiency anemia occurs in many pregnant women because their iron stores need to serve their own increased blood volume, as well as be a source of hemoglobin for the growing baby and for placental development.