Genital herpes, a sexually transmitted disease is one among the more frequently occurring conditions, with global prevalence estimated to be 400 million. Attributed to the herpes simplex virus, the condition is generally known to occur lifelong, with treatment regimens aimed at managing the condition. Herpes infections are known to reactivate periodically, and Valtrex is one among the different medications used in treating the condition. The medication is also used as part of treatment regimen for various other conditions. Subsequent sections offer a detailed view of the drug, including possible side effects of Valtrex, to help patients and caregivers manage and mitigate undesirable outcomes effectively.
Overview of Valtrex
Belonging to the category of antiviral drugs, Valtrex also known by its medicinal name of Valaciclovir, is a guanine nucleoside antiviral, used in treating the following conditions:
- Herpes infections (Herpes Labialis, genital herpes, genital herpes lesions, herpes zoster)
- Hepatitis (suppression of herpes in patients with Hepatitis)
- HIV (suppression of herpes in patients with HIV)
- Cytomegalovirus infections
Mechanism of action of Valtrex
A major portion of the mechanism of action of Valtrex is attributed to the properties and activity of acyclovir which selectively inhibits herpes virus. It is known to trigger in vitro activity against different types of herpes viruses – HSV, VZV, CMV, EBV, HHV-6. It is known to have a very high affinity for thymidine kinase, thereby resulting in high selective inhibition. The antiviral effects are primarily linked to properties of inhibition, termination and inactivation of viral DNA polymerase, viral DNA chain, and viral DNA polymerase respectively.
Precautions to be taken before taking Valtrex
To avoid the possibility of undesirable effects, it is necessary to take certain precautions. For instance, it is necessary to get blood count monitored when on the drug. This is because of the mechanism of action and the possible outcomes on patients with certain existing conditions. Individuals diagnosed with kidney related ailments are to intimate the treating doctor in advance, as the medication is known to have an impact on the kidneys of patients with existing renal complications. Depending on the condition, it may be necessary to either choose a different line of treatment, or to alter the dosage and schedule of the antiviral.
One of the reasons for adverse outcomes is incorrect dosage or intake schedule. It is necessary to diligently stick to the recommended dosage and the schedule of intake. Here is a small compilation of the ideal dosage for specific conditions. It is reiterated that these recommendations are only for the purpose of reference, and the actual dosage will be determined by the treating specialist. The actual dosage depends on a host of factors, such as the age of the patient, the gender, the condition being treated, the intensity of the condition, the overall health of the patient, existing ailments and medications in use. Typically, the dosage for patients with chicken pox is 20 mg for every kilo of body weight, and the medication is prescribed to be taken thrice a day for five days. For patients with cold sores, the ideal dosage is 2000 mg twice a day for adults and children above the age of twelve. For genital herpes and shingles the average dosage is 1000 mg twice a day for ten days.
Symptoms that indicate herpes, for commencing the medication
Ideally, the prescription medication is recommended to be started immediately on observing symptoms that indicate cold sores. For instance, a tingling sensation in the mouth, or a burning sensation in the mouth are indicative of cold sores. Similarly, an itching feeling is also regarded as one of the symptoms that point to the condition. When Valtrex is taken immediately after identifying the symptoms, there is the possibility of the medication preventing the formation of blisters, that are associated with cold sores. However, after the blisters have formed, the same results may not be experienced immediately.
The medication works by reducing the length of time that the cold sores are formed. Without the right kind of medication, cold sores may form and remain for close to two weeks; with Valtrex, the cold sores may last for a shorter period, depending on the condition and the dosage prescribed.
Compilation of possible side effects of Valtrex
All medications come with the possibility of undesirable effects. Attributed to the mechanism of action or the properties of active compounds, the effects may differ from person to person. Some are known to experience mild or moderate effects, while others are known to experience serious or adverse effects. The mild or moderate effects of medications typically resolve naturally, without the need for any medical intervention, however, the serious or adverse effects require medical attention at the earliest to prevent the condition from going out of hand. The following is a compilation of possible undesirable effects of Valtrex; it is necessary to note that this compilation is neither exhaustive nor complete. It is only intended to serve as a broad reference of the type of possible side effects. It is also necessary to add that many users of medications may not experience any side effects whatsoever.
Commonly reported side effects include possible pain in the abdomen and feelings of nausea. The patient may experience headache and this is relatively common among users of the medication for cold sores. However, the effects may slightly vary in terms in of intensity or duration when the medication is used for treating shingles.
Drug interactions of Valtrex
Most medications are known to have interactions with other medications and substances. This includes prescription medications, OTC formulation, herbal remedies, supplements, nutraceuticals, and alternative medicine. Depending on the importance of conflicting medications and substances, one of the two are either stopped temporarily, or the dosage and intake schedule are altered to prevent conflict. While Valtrex is not known to trigger major drug interactions that are a cause for concern, there is the possibility of interactions with certain medications, as listed – Dichlorphenamide, Leflunomide, Fexinidazole, Teriflunomide, Nitisinone or Foscarnet.
Valtrex when taken in combination with the following medications may aggravate the side effects of either of the two medications. As the medications belong to categories that make it necessary to be continued, the dosage and intake schedules of either of the medications are altered. This list includes – Fosphenytoin, Valproic Acid and Phenytoin.
Like most medications, Valtrex is also not free from the possibility of interaction with food habits or intoxicating substances. For instance, it may be necessary to abstain or reduce intake of alcohol and tobacco when on the medication. Similarly, it is necessary to discus details of recommended diets with the treating specialist, apart from the timing of intake of the medication. For instance, it may be necessary to take the medication only after food or only before food, depending on outcomes.
Instructions for certain categories of individuals
Most medications come with specific instructions to certain categories of users. This is necessary, as these categories of users may be required to either look at altered dosage, or intake, or seek specific medical advice regarding use of medication. To rest the apprehensions and allay fears of these categories of users, here is detailed information about risks linked to the medication. Information may also specifically convey that there is no risk associated with the medication for certain categories.
Patients with a history of allergies need to inform the specialist about the allergies. This applies to allergies to food products, animal dander, pollen, natural preservatives, coloring agents etc. While the standard practice is to check the ingredients for allergy inducing substances, it is necessary to specifically inform the doctor, as there is the possibility of certain actions causing reactions. Allergies have the risk of quickly developing into serious conditions from apparently trivial reactions. It is necessary to be on the lookout for tell tale symptoms of allergies such as hives, itches breathing difficulty, or difficulty in swallowing. These symptoms are indicative of a possible serious condition, that needs to be mitigated and treated on time.
All medications come with special instructions for use on pediatric patients. Pharmaceutical companies typically carry out in-depth studies on the effects of medications on pediatric patients, and this is the basis for the special instructions. However, Valtrex has not been studied for effects on pediatric patients. Therefore, there is no clear evidence of the effectiveness of the medication or the possibility of undesirable effects on children. Hence it is necessary to take the medication only after explicit recommendations by the doctor.
Similar to pediatric patients, medications for geriatric patients come with special instructions. This is also based on reports from studies about the efficacy of the medication and the possible side effects. Valtrex has not been studied in detail to understand more about the efficacy or the undesirable effects and it is therefore necessary to seek medical advice regarding its use. Additionally, it is also necessary to bear in mind that kidney degeneration is linked to aging and most aged individuals are likely to have relatively poor kidney functioning. This necessitates a change in dosage to prevent untoward outcomes.
Other categories of users who receive special instructions for all medications are pregnant women and women with suckling infants. Studies have not been conducted on the ill effects or the effectiveness of Valtrex on both these categories of users. It is therefore necessary for pregnant women and breastfeeding women to consult a specialist before use.
Medical conditions that may make patients unsuitable to rely on Valtrex
There is the possibility of patients with certain existing conditions experiencing side effects of Valtrex. For instance, patients who have undergone bone marrow transplantation or planning to undergo bone marrow transplantation are at risk of exposure to severe undesirable effects. Similarly, as outlined in earlier, patients diagnosed with HIV or AIDS are also unsuitable to receive treatment with Valtrex due to the possibility of strong effects.
In addition to kidney ailments, patients who have either undergone kidney transplantation or planning to undergo kidney transplantation are to look at other lines of treatment. These conditions expose the patients to very high levels of undesirable effects. One of the reasons for the impact of kidney functioning on the medication is the longer time required for the kidneys to process and eliminate the compounds from the body.