Hydroxychloroquine (brand name Plaquenil, Plaquenil Sulfate) is a medicine used to treat rheumatoid arthritis and other inflammatory conditions such as systemic lupus erythematosus (SLE/Lupus).
Hydroxychloroquine is also an antimalarial medicine used to prevent and treat malaria and other parasitic infections. It is not used routinely now for this purpose because of resistance by the parasites.
It is not clear how hydroxychloroquine works in inflammatory conditions; however it is thought to have an action on the immune system. In rheumatoid arthritis this action helps to reduce inflammation and thus reduce pain and swelling. It also limits damage to the joints and helps to prevent disability in the long term.
Because hydroxychloroquine acts to reduce the damage to the joints, rather than just relieve the pain, it belongs to the group of medicines called disease modifying antirheumatic drugs (DMARDs).
About 60% of people treated with hydroxychloroquine experience improvement in their condition.
Hydroxychloroquine does not work straight away. It may take 8 to 12 weeks for symptoms to start to improve. The full effect of treatment may take up to 26 weeks.
Other medicines may be given to improve your symptoms while waiting for hydroxychloroquine to work.
Hydroxychloroquine is taken by mouth in tablet form. The usual dose is one tablet (200mg) once or twice a day. Tablets can be taken altogether, once a day.
The dose may be reduced to a maintenance dose after a few months once a response is achieved. Occasionally it may be taken every second day.
It is best taken with food as it has a slightly bitter taste.
Hydroxychloroquine is not a pain killer and it should be taken continuously to be effective. Other medicines may be required to treat the pain.
Hydroxychloroquine may be used with other arthritis medicines including:
There are separate information sheets for the medicines mentioned above.
Treatment with hydroxychloroquine may be continued indefinitely as long as it is effective and no serious side effects occur.
If you stop hydroxychloroquine treatment for more than a few weeks there is a risk that your condition may worsen. Continue with your treatment unless advised by your doctor or unless side effects develop.
You might experience side effects with your treatment. Tell your doctor if you are concerned about possible side effects. A reduction in dose may minimise side effects so that you can continue to take this treatment. Your doctor will advise on any dose changes that are necessary.
About 10% of patients experience stomach and bowel side effects such as nausea (feeling sick), loss of appetite or diarrhoea. As the tablets are slightly bitter, these problems can often be reduced by taking the tablets with food or milk, or they may just improve with time.
This information has been produced by the Australian Rheumatology Association (ARA) to help you understand the medicine that has been prescribed for you. Please read it carefully and discuss it with your doctor. The information in this sheet has been obtained from various sources and has been reviewed by the ARA. It is intended as an educational aid and does not cover all possible uses, actions, precautions, side effects, or interactions of the medicines mentioned. This information is not intended as medical advice for individual problems nor for making an individual assessment of the risks and benefits of taking a particular medicine. It can be reproduced in its entirety but cannot be altered without permission from the ARA. The NHMRC publication: How to present the evidence for consumers: preparation of consumer publications (2000) was used as a guide in developing this publication.