Hydroxychloroquine

This leaflet has been written to provide information for patients about hydroxychloroquine. It tells you what it is, how it works, how it is used to treat skin conditions, and where you can find out more about it.

Hydroxychloroquine is one of several antimalarial drugs that have anti-inflammatory effects useful in other diseases.

Hydroxychloroquine is particularly effective for systemic lupus erythematosus (SLE) and discoid lupus erythematosus (DLE).

By reducing inflammation, hydroxychloroquine can decrease pain, swelling, and stiffness of joints, and improve or clear some rashes.

These include: 

• Various forms of lupus erythematosus 
• Sarcoidosis
• Porphyria cutanea tarda 
• Skin disorders caused or aggravated by the sun (photosensitive skin disorders)
• Granuloma annulare 
• Lichen planus
• Urticaria vasculitis 
• Sarcoidosis

Hydroxychloroquine does not work immediately, and it maybe 12 weeks or longer before any benefit is noted.

You should take hydroxychloroquine with or immediately after food.

Your doctor will advise you about this. Usually, you will be started on a full dose (for example, 400 mg daily or two tablets of 200mg hydroxychloroquine), and later your doctor may reduce the dose (for example, to 200 mg daily of hydroxychloroquine). Some patients may only need to take hydroxychloroquine two or three times per week or only during the summer months when their disease is well controlled. 

Side effects are uncommon; however, a few people may develop one of the following: rash, indigestion, diarrhea, headache, blurred vision, cramps or muscle weakness, darkening of the skin, or bleaching hair. Hydroxychloroquine can aggravate pre-existing psoriasis.

Considering the risks and benefits of taking hydroxychloroquine during pregnancy and breastfeeding, a systematic review and analysis of medical publications did not show any increased risk of death or defects in the fetus, spontaneous abortions, premature labor, or increased risk of stillbirth in patients with autoimmune diseases.

Before starting on hydroxychloroquine, your doctor may wish to carry out a blood test to check that your liver and kidneys are working normally. It should not be necessary to carry out regular blood tests. Your doctor should also enquire about any visual problems you may have and check your vision before starting you on the medication.

If you are likely to stay on hydroxychloroquine long term (5 years or more), your doctor may refer you to have a baseline hospital eye test within one year of starting the medication. After five years, you may be referred for annual eye screening.

Rarely, higher doses of hydroxychloroquine taken for a long period may damage the retina of the eye (the layer of cells in the back of the eye that detects light and allows you to see). This possible damage is prevented by keeping the dose low and monitoring the eyes closely if taking hydroxychloroquine for an extended period. 

There is no particular reason for you to avoid alcohol while taking hydroxychloroquine, although it is advisable to adopt sensible drinking habits in line with the NHS guidelines.

Most other drugs can be taken safely with hydroxychloroquine. There are important interactions with Amiodarone and Digoxin (taken for heart disease) and drugs used for epilepsy or depression.

However, if you start any new drugs, you should remind the doctor that you are already taking hydroxychloroquine. Indigestion remedies, including some that are sold over the counter, can stop hydroxychloroquine from being absorbed. Always discuss other medications with your doctor or pharmacist before taking them.

If you want to know more about hydroxychloroquine, or if you are worried about your treatment, you should speak to your doctor or pharmacist.