Acyclovir and Headaches: What Users Say

• MS1...
• March 13, 2014

For Herpes Zoster "I had a random herpes zoster outbreak (shingles) on my back and was prescribed 800 mg 5x a day for 7 days. It dried up my blisters within two days, and I healed nicely. I did, however, have headaches and dry mouth, with severe nausea and vomiting the last two days on the medication. Those are side effects, and being that I was on a strong dose, these side effects really affected me."

• Bal...
• Taken for 5 to 10 years
• April 19, 2020

For Herpes Simplex (HSV) "I was getting many cold sores every year. I would take Acyclovir as soon as the numbness started. It never shortened the duration; never had any effect on the pain. The cold sores just kept getting worse. The doctor finally put me on a stronger anti-viral. It did nothing either. I only got headaches from the anti-virals. I finally decided to try vitamin D. I haven't had a cold sore in at least 2 years."

• Krr...
• Taken for less than 1 month
• July 16, 2016

Acyclovir for Herpes Simplex (HSV) "I had a sudden onset of cold sores, and a new one was appearing each day. I am on immunosuppressants, so my body just can't fight this virus on its own. After 5 days, I went to my doctor. This medication was amazing-within 24-48 hrs, the blisters were crusting over. The swelling and redness were decreasing as well. I am on 400 mg 3 x daily for 10 days. I am currently on day 6. For the first few days, I would feel lightheaded (not dizzy) for a few hours after each dose, but that has gone away now. No nausea when taken with food. I did have a few mild headaches, but that was because I was not drinking enough fluid. As soon as I hydrated, headaches were gone. My doctor gave me 2 refills, so next time I feel the onset, I can start treatment right away."

• Thr...
• Taken for 1 to 6 months
• July 29, 2020

For Herpes Simplex (HSV) "I was diagnosed with herpes this year after getting it from my partner. I had a fairly bad first outbreak on my inner labia and just presumed it to be from shaving, but I went to a sexual health clinic and got diagnosed. This medicine has been so helpful. Anytime I have a tingling/throbbing sensation, I take it, and it works wonders. I’m currently taking it at the moment, and the only real side effect I have is having a headache!"

• pop...
• Taken for less than 1 month
• August 20, 2022

For Herpes Zoster "I have been taking acyclovir 800 mg 5 times per day for 8 days for shingles (2 days more to go). I had a headache and nausea for the first couple of days taking this. The headache went away, but I still feel nauseated most of the time. I am also lightheaded, and the dizziness increases when I walk around at all. I feel very fatigued. Sometimes I have felt really agitated, like I wanted to crawl out of my skin. It has caused frequent bowel movements and some diarrhea. Between the shingles pain and the side effects, I am nearly housebound. I've been sick for a month (the rash didn't appear for 3 weeks). I'm at the end of my rope and cannot wait to get off this drug. I had shingles 8 months ago and couldn't tolerate the valacyclovir then - now that it's returned, my doctor insists I must take this to get the virus out of my system. I pray that it works. I am 64 and small build (110 pounds). I do tend to be sensitive to drug side effects."

• Anonymous
• October 19, 2011

For Herpes Simplex (HSV) "I'm 25, and I've always had cold sores in my mouth since I was 4, and it can happen with sun or eating citrus. It's only getting worse now that I have braces, so my orthodontist told me about this pill and my doctor gave it to me, and I love it, EXCEPT I get a headache, fatigue, dizziness, and joint pain... but it's totally worth it!"

• Kay...
• Taken for less than 1 month
• December 17, 2020

For Herpes Zoster "I took Acyclovir because of shingles. I had to take 800 mg 5x a day for 7 days. On the first day, I was okay, second day, I felt dizzy and a little nauseous, third day, I had severe nausea, which was horrible. Other symptoms included feeling spaced out, stomach cramping, headache, and sweating when I was asleep. It’s better to finish the course, which I managed to do-thank God! However, it did clear my rash away."

• Ric...
• January 2, 2017

For Cold Sores "I felt a fever blister (cold sore) coming on, so I began 400 mg of acyclovir 3 times a day. After the second day, I experienced a headache that was very uncomfortable. My early cold sore did not progress into an unsightly and painful sore. I am treating the headache with 500 mg Tylenol once a day."

• RGa...
• June 16, 2016

For Cold Sores "Tried this for CS outbreak. I'll keep it simple and to the point. Pros: - Works a lot better than any OTC (throw that junk out, waste of $) - Cheap... compared to other drugs - Fast acting... even if caught later, will still work - Can stop/reduce symptoms - Convenient vs. any cream - Side effects nothing like Famvir. Cons: - Not as good as Famvir (holy grail to knockout cold sores) - It appears you need to double the dose to really get an effect - Maybe slight headache - You need to take a lot, it's not just 3 pills and done... - No advancement in this drug, and it's been around for how long?? - Did get a second outbreak while taking... but cleared up quick."