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Sitavig Side Effects Center
Medical Editor: Melissa Conrad Stöppler, MD
Sitavig (acyclovir) is prescribed to treat recurrent cold sores. Sitavig belongs to a category of drugs called antiviral medications. Common side effects from the use of Sitavig can include headache and pain at the site of application.
Sitavig is available as one 50 mg buccal tablet that is applied to the upper gum region inside the mouth. Drug interactions are unlikely.
Sitavig has not been studied in pregnant or breastfeeding women.
Our Sitavig (acyclovir) Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
What is Prescribing information?
The FDA package insert formatted in easy-to-find categories for health professionals and clinicians.
Sitavig FDA Prescribing Information: Side Effects
Clinical Trial Experience
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.
The overall safety of SITAVIG was assessed in 378 adult subjects having at least 4 herpes labialis episodes the previous year.
One randomized, double-blind, placebo controlled trial was conducted in patients with recurrent herpes labialis (cold sores). In this trial, 378 HSV infected subjects used SITAVIG as a single dose, and 397 subjects used placebo.
Selected treatment emergent adverse events without regard to causality and reported in at least 1% of patients can be seen in Table 1.
Table 1 : Selected Treatment Emergent Adverse Events
reported in at least 1% of patients
N = 378
N = 397
|Nervous System Disorders|
|Gastrointestinal system Disorders|
|Administration Site Conditions|
|Application Site Pain||1%||1%|
|Application Site Irritation||1%||0|
|Skin and Subcutaneous Disorders|
The treatment emergent adverse events considered related to treatment that occurred in greater than or equal to 1% of patients included headache (1% SITAVIG vs. 2% placebo) and application site pain (1% both arms). There was no discontinuation of SITAVIG due to adverse drug reactions. Most treatment related adverse events were mild or moderate in severity. One report of headache from both treatment arms was classified as severe.
Read the entire FDA prescribing information for Sitavig (Acyclovir Buccal Tablets)
Additional Sitavig Information
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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