Understanding Aciclovir Side Effects and Solutions
Common Side Effects of Cold Sore Tablets
Aciclovir tablets, the primary treatment for cold sores available through EverydayMeds, may cause side effects in some patients. The most frequently reported reactions include nausea, headache, dizziness, and stomach discomfort. These effects typically occur in fewer than 1 in 10 people and are usually mild and short-lived.
Managing Gastrointestinal Side Effects
Stomach upset is among the most common concerns with oral aciclovir. Taking your medication with food or milk can significantly reduce nausea and stomach irritation. If you experience persistent digestive issues, splitting your daily dose throughout the day may help. Our 400mg aciclovir tablets can be taken with meals to minimise these effects while maintaining therapeutic effectiveness.
Addressing Headaches and Dizziness
Some patients report headaches or mild dizziness when starting aciclovir treatment. Staying well-hydrated and avoiding sudden position changes can help manage these symptoms. If headaches persist or worsen, paracetamol or ibuprofen may provide relief, though you should consult with our pharmacists about appropriate pain management options.
Recognising Serious Side Effects
While rare, serious allergic reactions can occur with any medication. Signs requiring immediate medical attention include severe skin rash, difficulty breathing, swelling of face or throat, or unusual bleeding. EverydayMeds emphasises the importance of reading patient information leaflets and understanding when to seek urgent medical care.
Alternative Treatment Options
For patients who cannot tolerate oral aciclovir, EverydayMeds offers alternative approaches. Topical aciclovir 5% cream provides localised treatment with minimal systemic side effects. Valaciclovir tablets represent another option, often requiring fewer daily doses and potentially causing fewer gastrointestinal side effects due to better absorption.
When to Contact Healthcare Professionals
If side effects persist beyond the first few days of treatment, worsen over time, or interfere with daily activities, contact our pharmacy team or your healthcare provider. EverydayMeds pharmacists can provide guidance on managing minor side effects and determining when medical review might be necessary for your cold sore treatment plan.






