What are the side effects of shingles treatment?
Like all medications, antivirals can cause side effects in some people.
Common side effects of aciclovir include:
- headaches
- nausea (feeling sick)
- vomiting (being sick)
- dizziness, especially when standing up
- diarrhoea
- stomach pains
- rash
- the skin being more sensitive to light (photosensitivity)
- itching
- feeling tired
- fever (high temperature)
Uncommon side effects of aciclovir include:
- itchy rash (hives)
- hair loss
Very rare side effects of aciclovir include:
- weakness
- agitation or confusion
- tremors
- hallucinations (seeing or hearing things that aren’t there)
- seizures (fits)
- drowsiness
- unsteadiness and lack of coordination
- coma
- paralysis (being unable to move part or all of the body)
- stiff neck and sensitivity to light
- yellowing of the skin and the whites of the eyes (possible liver problems)
- passing little or no urine (possible kidney problems)
- lower back pain
- swelling of the face, lips, and tongue, difficulty breathing, rash, and collapse (a possible severe allergic reaction called anaphylaxis)
If you experience any of these side effects, stop taking your medication and see a doctor as soon as possible.
Common side effects of valacyclovir include:
- headache
- nausea (feeling sick)
- dizziness
- vomiting (being sick)
- diarrhoea
- the skin being more sensitive to light (photosensitivity)
- rash
- itching
Uncommon side effects of valacyclovir include:
- confusion or agitation
- seeing or hearing things that aren’t there (hallucinations)
- drowsiness
- tremors
- shortness of breath
- stomach pain
- itchy rash
- lower back pain
- blood in the urine
Rare side effects of valacyclovir include:
- unsteadiness and poor coordination
- slow, slurred speech
- seizures (fits)
- coma
- confused or disturbed thoughts
- passing little or no urine (possible kidney problems)
- swelling of the face, lips, and tongue, difficulty breathing, rash, and collapse (a possible severe allergic reaction called anaphylaxis)
If you experience any of these side effects, stop taking your medication and see a doctor as soon as possible.
Common side effects of famciclovir include:
- headache
- nausea (feeling sick)
- vomiting (being sick)
- stomach pain
- diarrhoea
- dizziness
- itchy rash
Uncommon side effects of famciclovir include:
- confusion
- drowsiness
- itchy rash with irregular raised bumps (hives)
Rare side effects of famciclovir include:
- hallucinations (seeing or hearing things that are not really there)
- awareness of your own heartbeat, fast or irregular heartbeat (palpitations)
- severe blisters on the skin, lips, eyes, mouth, inside the nose, or genitals (possible severe allergic skin reaction)
- swelling below the surface of the skin (angioedema)
- unexplained bruising, or bleeding (including nosebleeds)
- yellowing of the skin and the whites of the eyes (possible liver problems)
- red or purple discolouration of the skin which doesn’t fade
- seizures (fits)
- swelling of the face, lips, and tongue, difficulty breathing, rash, and collapse (a possible severe allergic reaction called anaphylaxis)
If you experience any of these side effects, stop taking your medication and see a doctor as soon as possible.
How long do these side effects last?
Most side effects of antivirals are mild and go away on their own. If your side effects are bothering you, are getting worse, or not going away, speak to your pharmacist or GP.
If you experience serious side effects while taking antivirals, seek immediate medical attention.
What to do if you get side effects
If you experience mild side effects while taking antivirals, there are a few things you can do to prevent or reduce them, such as:
- taking your medication exactly as directed by a doctor
- taking your medication with or after food. This may reduce gastric symptoms such as nausea and vomiting
- spreading your doses evenly apart
- keeping a journal noting what your side effects are, when they occur, and how long they last. This may be helpful for your pharmacist or GP to see what is causing your side effects
- asking your GP or pharmacist for advice
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