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Abreva vs Valtrex

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Comparative Analysis


For patients with herpes simplex virus (HSV), including cold sores or fever blisters, certain medications that inhibit the multiplication of viral cells can help manage symptoms and reduce the frequency of outbreaks. Abreva and Valtrex are two such drugs commonly prescribed for HSV. Both have different mechanisms of action but are effective in treating herpes related conditions.

Abreva is a topical treatment containing docosanol, an antiviral agent that prevents the virus from penetrating healthy skin cells, thus limiting its spread and reducing healing time. It's available over-the-counter and should be applied at the first sign of a blister.

Valtrex, on the other hand, is an oral medication classified as a nucleoside analogue antiviral drug. Its active ingredient valacyclovir inhibits viral DNA replication by competing with deoxyguanosine triphosphate for incorporation into viral DNA. This interferes with the viruses' ability to replicate within host cells thereby shortening outbreak duration and decreasing severity.

Abreva vs Valtrex Side By Side

Brand NameAbrevaValtrex
ContraindicationsAllergy to docosanol or any component of the formulationAllergy to valacyclovir, acyclovir, or any component of the formulation; certain types of medication for HIV/AIDS
CostAround $18 for a 2g tube (brand name), averages at about $13 for a 2g tube (generic)Approximately $130 for 30 tablets of 500 mg (brand name), about $27 for thirty 500mg tablets (generic)
Generic NameDocosanolValacyclovir
Most Serious Side EffectSigns of allergy like rash, itching or hives on the skin; swelling of the face, lips, tongue or other parts of the body; shortness of breath, wheezing or trouble breathingMental/mood changes (such as agitation, confusion), kidney problems (change in amount/color of urine), extreme tiredness, fast/slow/irregular heartbeat, fainting spells, low sodium level symptoms; headache, difficulty concentrating, memory problems, feeling unsteady/confusion, severe allergic reactions such as anaphylaxis
Severe Drug InteractionsNot specifically mentioned, but always inform your healthcare provider about all medications you are takingCertain types of medication for HIV/AIDS; potential for increased side effects or reduced efficacy when taken with drugs affecting kidney function
Typical DoseApply approximately five times a day until the cold sore has completely healed500–1000 mg/day depending on the condition being treated. For recurrent episodes of genital herpes or cold sores, 500 mg twice a day for three days. For shingles, 1 gram three times daily for seven days

What is Abreva?

Docosanol (the generic name for Abreva) is a widely used over-the-counter topical medication typically applied to the lips or face, designed to inhibit cold sores and fever blisters caused by the herpes simplex virus. It was first approved by the FDA in 2000. Abreva works by blocking the virus from entering healthy skin cells, effectively reducing both healing time and symptom severity if applied early enough.

On the other hand, Valacyclovir (Valtrex) is an antiviral oral medication that requires a prescription from a healthcare provider. FDA-approved since 1995, Valtrex interferes with the virus's ability to replicate itself within your body’s cells which helps reduce outbreak duration and intensity.

Both medications are well-tolerated with minimal side effects; however, like all medications they could cause adverse reactions in certain individuals. While Abreva has limited systemic absorption resulting in fewer side effects compared to oral therapy, it only treats symptoms on site of application whereas Valtrex can help manage outbreaks throughout the entire body.

What conditions is Abreva approved to treat?

Abreva and Valtrex are both approved for the treatment of herpes simplex virus infections, specifically:

  • Cold sores or fever blisters on the face or lips (Abreva is a topical medication)
  • Genital herpes in immunocompetent adults (Valtrex is an oral medication also used for cold sores, chickenpox, and shingles)
  • Herpes labialis (cold sores) prophylaxis in immunocompromised adults

How does Abreva help with these illnesses?

Abreva helps to manage cold sores by blocking the virus that causes them from entering into healthy skin cells. It does this by inhibiting the viral particle from fusing with the lipid bilayer of cell membranes, preventing replication and spread of the virus. Herpes simplex is a type of virus, a microscopic infectious agent, that plays an important role in causing outbreaks of cold sores on or around your mouth. It is thought that individuals with weakened immune systems are more susceptible to herpes simplex infections. Therefore, by blocking herpes simplex entry into cells, Abreva can limit new growth and development of cold sores and help patients manage their condition and reduce outbreak duration.

What is Valtrex?

Valtrex, the brand name for valacyclovir, is an antiviral medication used in the management of herpes simplex, herpes zoster (shingles), and herpes B. It works by slowing down the growth and spread of the virus so that the body can fight off infection more effectively. Valacyclovir was first approved by FDA in 1995. Unlike topical treatments such as Abreva which are applied to surface lesions directly and primarily manage symptoms at a local level, Valtrex works systemically after absorption from gastrointestinal tract to inhibit viral replication throughout your body. Its systemic action means it has a different side-effect profile than topical agents like Abreva; potential side effects can include headache, nausea or vomiting - though these are generally rare. The broad spectrum activity of Valtrex may be particularly beneficial for patients with severe or widespread outbreaks not adequately managed by topical medications alone.

What conditions is Valtrex approved to treat?

Valtrex is a prescription medication approved for the treatment of several conditions related to herpes virus infections, such as:

  • Cold sores (herpes labialis)
  • Genital herpes in immunocompetent patients
  • Shingles (herpes zoster) It can also be taken to prevent these outbreaks in adults and adolescents who are at least 12 years old.

How does Valtrex help with these illnesses?

Valacyclovir, the active ingredient in Valtrex, is an antiviral medication that interferes with the replication process of herpes simplex viruses. It does so by inhibiting a viral enzyme necessary for the virus to multiply, thereby reducing the severity and duration of outbreaks. Unlike Abreva which acts locally on the skin where it's applied, Valacyclovir works systemically once absorbed into your bloodstream and can reach all sites in your body where herpes virus might be hiding including those not accessible by topical agents. This makes Valtrex especially effective at treating recurrent outbreaks or when taken as suppressive therapy to reduce frequency of outbreaks. Additionally, while Abreva is primarily used for relieving symptoms associated with cold sores (herpes labialis), Valtrex is also prescribed for genital herpes and shingles due to its broader spectrum of action.

How effective are both Abreva and Valtrex?

Both docosanol (Abreva) and valacyclovir (Valtrex) have a well-established history in treating cold sores caused by the herpes simplex virus, and were approved by the FDA several years apart. They operate on different mechanisms, with Abreva acting as a barrier to prevent viral entry into cells while Valtrex interferes with viral replication once it has entered the cell. The effectiveness of both Abreva and Valtrex was directly studied in various clinical trials; they exhibited similar efficacy in managing symptoms of herpes outbreaks.

A 2001 double-blind study found that patients applying Abreva at onset saw reduction in healing time compared to placebo. Its side effect profile is relatively mild due to its topical nature, primarily limited to skin irritation where applied. As an over-the-counter medication, it remains one of the most accessible treatments for cold sore management.

Valtrex's approval came earlier than Abreva's and research shows that when taken within 24 hours from onset of initial symptoms such as tingling or redness, Valtrex can reduce outbreak duration significantly over placebo groups. Despite being prescription-only unlike Abreva, its systemic action allows it not only treat current outbreaks but also help suppress future ones especially for individuals having frequent recurrences.

While both drugs are effective individually against HSV-1 infections causing oral cold sores, deciding between them often comes down patient-specific factors like cost considerations due to insurance coverage differences and personal preference towards topical versus oral administration routes among others.

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At what dose is Abreva typically prescribed?

Topical doses of Abreva should be applied approximately five times a day until the cold sore has completely healed. It's best to start applying Abreva at the first sign of a cold sore for maximum effectiveness. On the other hand, Valtrex is an oral medication primarily used for treating herpes infections including cold sores. The usual dosage for adults with recurring cold sores is 2 grams every 12 hours, two times (for one day). This treatment can also be started at the first signs of a cold sore outbreak but always follow your healthcare provider's instructions.

At what dose is Valtrex typically prescribed?

Valtrex treatment is typically initiated at a dosage of 500–1000 mg/day, depending on the condition being treated. The dose can then be adjusted based on your doctor's recommendation. For recurrent episodes of genital herpes or cold sores, the usual dose is 500 mg twice a day for three days. For shingles, the dosage is usually 1 gram three times daily for seven days. However, this may vary if there's no response to initial treatment after a certain period or according to specific patient characteristics such as kidney function. It's important to take each dose with plenty of water and space doses evenly throughout the day.

What are the most common side effects for Abreva?

Common side effects of Abreva, which is a topical cream for cold sores, include:

  • Skin irritation where the product was applied
  • Redness
  • Dryness

On the other hand, Valtrex (Valacyclovir), an oral medication used to treat herpes virus infections including shingles, genital herpes and cold sores can have more systemic side effects that may include:

  • Nausea
  • Stomach pain
  • Dizziness
  • Headache
  • Depression or other mood changes
  • Rash or itching skin

Always remember to inform your healthcare provider about any unusual symptoms after starting a new medication.

abstract image of a patient experiencing side effect

Are there any potential serious side effects for Abreva?

While both Abreva and Valtrex are effective in treating cold sores, they may cause different side effects. In rare cases, potentially serious side effects can occur with each medication:


  • Signs of allergy like rash, itching or hives on the skin
  • Swelling of the face, lips, tongue or other parts of the body
  • Shortness of breath, wheezing or trouble breathing


  • Mental/mood changes (such as agitation, confusion)
  • Kidney problems (change in amount/color of urine)
  • Extreme tiredness
  • Fast/slow/irregular heartbeat -Fainting spells
    -Low sodium level symptoms; headache, difficulty concentrating , memory problems , feeling unsteady/confusion. -Severe allergic reactions such as anaphylaxis which includes symptoms like severe rash/blisters/hive, fever/chills ,swelling especially around face and neck area along with difficulty swallowing.

If you experience any severe adverse reactions to either treatment option it is critical that you seek medical attention immediately.

What are the most common side effects for Valtrex?

Valtrex, a systemic medication for herpes outbreaks, can cause potential side effects such as:

  • Nausea and stomach pain
  • Vomiting
  • Dizziness and headache
  • Agitation or confusion in severe cases
  • Mild skin rash
  • Joint pain or muscle discomfort.

It's important to note that these are possible side effects and not everyone who takes Valtrex will experience them. If any of these symptoms persist or worsen, seek medical attention immediately.

Are there any potential serious side effects for Valtrex?

Valtrex, while a highly effective antiviral medication for herpes outbreaks, may also cause certain side effects that could require immediate medical attention. These include:

  • Signs of an allergic reaction such as hives; difficulty breathing; swelling in your face or throat
  • Unusual changes in mood or behavior including confusion and potential hallucinations
  • A rare possibility of red blood cell disorder symptoms like fever, easy bruising or bleeding;
  • Kidney problems indicated by pain in your lower back along with drowsiness and mood changes
  • Liver problems manifested through upper stomach pain, loss of appetite followed by jaundice (yellowing of the skin or eyes)

If you observe any of these symptoms after taking Valtrex, seek immediate medical help.

Contraindications for Abreva and Valtrex?

Both Abreva and Valtrex, along with most other antiviral medications, may cause side effects in some people. If you notice your condition worsening or the development of new symptoms such as rash, hives, swelling of face/lips/tongue/throat/eyes/hands/feet/ankles/lower legs; hoarseness or difficulty swallowing/breathing after taking these drugs please seek immediate medical attention.

Neither Abreva nor Valtrex can be taken if you are taking certain types of medication for HIV/AIDS. Always tell your physician which medications you are using; these drugs will require a period to clear from the system to prevent potential dangerous interactions with Abreva and Valtrex. Additionally, it's important to mention any kidney problems when being prescribed Valtrex as this could affect dosing requirements.

How much do Abreva and Valtrex cost?

For the brand name versions of these drugs:

  • The price of a 2g tube of Abreva (10% Docosanol) averages around $18, which works out to about $6/day if used three times daily as recommended.
  • The price for 30 tablets of Valtrex (500 mg) is approximately $130, working out to roughly $4.33/day.

Thus, despite being an over-the-counter remedy, Abreva can be more expensive on a per-day treatment basis than prescription-only Valtrex if you are applying it frequently throughout the day. Please note that cost should not be your primary consideration in determining which drug is right for you and its effectiveness against herpes simplex virus infections.

Regarding generic options:

  • Generic docosanol cream prices vary but average at about $13 for a 2g tube.
  • Valacyclovir (generic Valtrex), costs about $27 for thirty 500mg tablets.

Again, while the initial purchase price may seem higher for valacyclovir compared with docosanol cream, when used regularly as part of your management plan, valacyclovir may prove more cost-effective on a per-day treatment basis.

Popularity of Abreva and Valtrex

Abreva (Docosanol) and Valtrex (Valacyclovir) are both used to treat symptoms of herpes simplex, a virus that causes cold sores around the mouth and other areas.

In 2020, it was estimated that Abreva, an over-the-counter topical medication for treating cold sores, was purchased by approximately 5 million people in the United States. It is considered one of the most popular non-prescription treatments for this predicament.

Meanwhile, Valtrex - a prescription antiviral medicine - had about 4 million prescriptions filled in the US during the same year. This drug is commonly prescribed not only for oral herpes but also for genital herpes and shingles. The prevalence of Valacyclovir has been steadily increasing over the past decade due to its effectiveness against various strains of herpes viruses.


Both Abreva (docosanol) and Valtrex (valacyclovir) have long-standing records of usage in patients with herpes simplex virus, specifically cold sores, and are backed by numerous clinical studies indicating that they are more effective than placebo treatments. Due to their different mechanisms of action -- Abreva acting primarily on the viral envelope preventing the virus from entering cells, whereas Valtrex is an antiviral medication that interferes with the replication process -- they tend to be used under different circumstances.

Abreva is considered a first-line treatment option available over-the-counter for early stage or mild outbreaks. On the other hand, Valtrex which requires a prescription would usually be recommended for severe outbreaks or for patients who experience frequent episodes.

Both drugs come in generic forms representing considerable savings especially for those paying out-of-pocket. The effect may not be noticeable immediately as both medications require some time to exert their full effects.

The side effect profile differs between these two drugs; while both generally well-tolerated, Valtrex has potential systemic side effects like nausea and headache compared to topical Abreva's local skin reactions such as dryness or itching at application site. For both medications it is important to apply/start them at earliest sign of outbreak and consistently follow instructions on use.