How does diclofenac work?
Diclofenac is a non-steroidal anti-inflammatory drug (NSAID). It works by reducing hormones that cause inflammation and pain in the body.
When you apply diclofenac gel, plasters or patches to your skin, it works in the same way as when you take it as a tablet or capsule. But the gel, plaster or patch only works on the area you have put it on.
How long does it take to work?
Diclofenac takes 20 to 30 minutes to work if you take it as tablets or capsules.
Suppositories take a few hours to work.
If you're using diclofenac gel, plasters or patches on your skin, it usually takes 1 to 2 days to work. For arthritis, you may need to use the gel for up to 7 days on the painful joint to feel the full effect.
Are there any long-term side effects?
Diclofenac tablets and capsules can cause an ulcer in your stomach or gut if you take them for a long time or in big doses.
There's also a small risk of heart failure or kidney failure if you take the maximum dose of 150mg a day for a long time.
It's best to take the lowest dose that works for the shortest possible time.
If you need to take diclofenac very often or you're taking a big dose, talk to your doctor about the best way to treat your pain.
Are there other treatments for pain and inflammation?
The type of painkiller that's best depends on what type of pain you have and the cause of your pain.
Diclofenac is a non-steroidal anti-inflammatory drug (NSAID). Ibuprofen and naproxen also belong to this group of painkillers.
If you need to take an NSAID long term, your doctor or pharmacist may recommend ibuprofen or naproxen instead of diclofenac. This is because it's less likely to cause heart problems.
If NSAIDs do not get rid of your pain, you can try painkillers that you can buy from pharmacies and shops, such as paracetamol or co-codamol (paracetamol combined with low-dose codeine).
If the medicine you buy is not controlling your pain, your doctor may recommend additional treatment to help your pain, such as exercise or physiotherapy.
Diclofenac does not work for some types of pain, such as nerve pain. Your doctor will have to prescribe a different medicine to treat peripheral neuropathy (nerve pain).
Is it addictive?
No, diclofenac is not addictive, but it's important to always take it as prescribed.
What will happen if I stop taking diclofenac?
When you stop taking diclofenac tablets or capsules, or stop using the suppositories, the effects will wear off after about 15 hours.
When you stop using the gel, plasters or patches, the effects will wear off after 1 or 2 days.
Will it affect my contraception?
Diclofenac will not affect any contraceptives, including the combined pill, the progestogen-only pill or emergency contraception.
However, if you take contraceptive pills and you're being sick or have severe diarrhoea for more than 24 hours, your contraception may not protect you from pregnancy. Check the pill packet for advice.
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Can I drive or ride a bike?
It happens rarely, but some people can feel tired, dizzy or sleepy when they take diclofenac. They may also have problems with their eyesight.
If diclofenac affects you in this way, do not drive or ride a bike until it passes and you feel OK again.
It's an offence to drive a car if your ability to drive safely is affected. It's your responsibility to decide if it's safe to drive. If you're in any doubt, do not drive.
For more information on the law on drugs and driving, visit GOV.UK.
Can I drink alcohol while taking or using diclofenac?
Yes, you can drink alcohol while taking diclofenac, but stick to the national guidelines of no more than 14 units a week for men and women.
Drinking too much alcohol may irritate your stomach. There's a risk you could get a stomach ulcer.
Is there any food or drink I need to avoid?
Apart from not drinking too much alcohol, you can eat and drink normally while taking diclofenac.