High blood pressure in the lungs (pulmonary hypertension) is a rare complication of systemic sclerosis, but you should have regular tests to check how well your lungs and heart are working which will pick up any problems. If necessary, pulmonary hypertension can be treated with specific drugs such as Bosentan, Sildenafil or Iloprost that improve symptoms such as breathlessness.

Two tablets are usually taken twice a day (in the morning and evening), although the dosage can sometimes vary. You may need to spend a day in hospital when you start treatment. If your condition has not improved after 8-16 weeks, or if it has got worse, you may be given additional treatment as well as, or instead of, Bosentan.

The side effects of Bosentan are that it can increase levels of some enzymes in the liver, which can cause liver damage. It may also cause anaemia in some people. As a result, your liver will need to be monitored once a month for as long as you are taking Bosentan.

Fluid retention – for example, leg swelling – has been reported in up to 30% of patients using Bosentan.

Bosentan may not be suitable for you if you:

  • already have a problem with your liver;
  • are taking Ciclosporin (a medicine that suppresses your immune system);
  • are pregnant - This type of medication can interact with hormonal contraception, such as the combined contraceptive pill, so it's better to use an alternative method, such as condoms.

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