Hydroxychloroquine

Hydroxychloroquine is a disease-modifying anti-rheumatic drug (DMARD). It regulates the activity of the immune system, which may be overactive in some conditions. Hydroxychloroquine can modify the underlying disease process, rather than simply treating the symptoms.

Hydroxychloroquine is used to treat:

• rheumatoid arthritis
• discoid and systemic lupus erythematosus (SLE)
• juvenile idiopathic arthritis (JIA).

Over the long term hydroxychloroquine can reduce pain, swelling and joint stiffness. If you have lupus, it may also improve the rash. It may be as long as 12 weeks before you notice the benefits.

Hydroxychloroquine is often taken in combination with other drugs such as methotrexate.

Are there any reasons I won't be prescribed hydroxychloroquine?

Before starting on hydroxychloroquine your doctor may take a blood test to check that your liver and kidneys are working normally, but you won't need any regular blood tests during the treatment.

Your doctor will ask you about any problems with your eyesight and may suggest you have a vision test. Hydroxychloroquine won't usually be prescribed if you have maculopathy, problems with the central part of the retina in the eye.

Hydroxychloroquine is taken in tablet form, with or after food.

Your doctor will advise you about the correct dose. Usually you will start on a full dose of 200–400 mg daily, and later your doctor may reduce this. When your condition is very well controlled you may be advised to take hydroxychloroquine only 2–3 times per week.

Hydroxychloroquine doesn’t work immediately. It may be 12 weeks or longer before you notice any benefit. Because it's a long-term treatment it's important to keep taking hydroxychloroquine unless you have severe side effects:

• even if it doesn't seem to be working at first
• even when your symptoms improve (to help keep the disease under control).

Side effects aren't common. However, in some people hydroxychloroquine can cause:

• skin rashes, especially those made worse by sunlight
• feeling sick (nausea) or indigestion
• diarrhoea
• headaches
• bleaching of the hair or mild hair loss
• tinnitus (ringing in the ears)
• visual problems.

There's a small risk that hydroxychloroquine can damage a part of the inside of the eye called the retina. And this increases with long-term use and higher dosage.

Your doctor will advise you on a safe dose to take according to your weight, and you will need to have regular monitoring of your eyes.

This monitoring of your eyes may be arranged at a hospital clinic when you start the drug and then again once a year in a hospital when you have been taking the drug for more than five years.

Otherwise, you should have a check up with an optician once a year and tell them that you're taking hydroxychloroquine.

You should report any new eye symptoms to your doctor straight away.

If you develop any other new symptoms or there's anything else that concerns you after starting hydroxychloroquine, you should tell your doctor or rheumatology nurse specialist as soon as possible.

Hydroxychloroquine is commonly used alongside other disease-modifying drugs including methotrexate – especially for rheumatoid arthritis.

However, some drugs can interact with hydroxychloroquine. Indigestion remedies (for example, antacids including some over-the-counter preparations) can stop hydroxychloroquine being absorbed. It's recommended you wait at least four hours after taking hydroxychloroquine before you take an indigestion remedy.

Discuss any new medications with your doctor before starting them, and always mention you're on hydroxychloroquine if you're treated by anyone other than your usual healthcare team.

Some types of antibiotics, called macrolides, may increase the risk of problems with the heart or circulation if taken while you're on hydroxychloroquine. These drugs, which include azithromycin, erythromycin and clarithromycin, won't usually be prescribed if you're already on hydroxychloroquine.

• You can carry on taking a non-steroidal anti-inflammatory drug (NSAID) or painkillers, if needed, unless your doctor advises otherwise.
• Don't take over-the-counter preparations or herbal remedies without discussing this first with your healthcare team.

Vaccinations

You can have vaccinations, including live vaccines such as yellow fever and shingles, while you're on hydroxychloroquine.

Even though hydroxychloroquine is an anti-malarial drug, don't assume it will protect you if you're travelling to an area where there's a risk of malaria. Always check with a healthcare professional what precautions you need to take against malaria.

There's no known interaction between alcohol and hydroxychloroquine.

However, if you're also taking methotrexate you should keep well within the recommended limits (no more than 14 units of alcohol per week for adults) as methotrexate can interact with alcohol and affect your liver. In some circumstances your doctor may advise lower limits.

We suggest you discuss your medication with your doctor if you're planning to have a baby, become pregnant or are thinking of breastfeeding.

Current guidelines state that hydroxychloroquine can be taken during pregnancy. It's often best to continue with it to prevent a flare-up of your condition as the benefits usually outweigh any possible risks.

You can also breastfeed while you're on hydroxychloroquine. Hardly any of the drug passes into the breast milk and there's no evidence it has any effect on the baby.