Thalidomide

Thalidomide is a medication used to treat bleeding from abnormal blood vessels called vascular malformations, in particular, fast-flowing arteriovenous malformations (AVM). These conditions can cause repeated bleeding, low blood counts, and the need for blood transfusions, especially when other treatments have not worked.

• How does thalidomide work?
  Thalidomide helps by blocking the growth of new abnormal blood vessels (anti-angiogenic effect) and reducing inflammation. It lowers the levels of certain proteins, like vascular endothelial growth factor (VEGF), that make blood vessels grow and leak.
  
  
• How is thalidomide taken?
  Thalidomide is taken orally. For patients with severe symptoms, thalidomide may be started at 200mg daily for 5 to 7 days for a rapid response. This is followed by a lower dose of 50mg daily which is better tolerated. If you have had embolisation or surgical resection, your doctor may begin with a low-dose regimen (50mg daily) started at least 1 week before until 3 to 6 months after embolisation sessions or surgical resection. The dose and length of treatment will also depend on your condition, how you respond to the medicine and side effects that you may have. In patients who are not able to have surgical resection or embolisation, long-term treatment with low dose thalidomide of 50mg every other day or twice a week may be required. You should always take thalidomide exactly as prescribed.
  
  
• What are the benefits?
  Thalidomide can reduce or stop bleeding episodes in most patients with AVM. Studies show that more than half of patients have no further bleeding after a course of treatment, and many need fewer transfusions and hospital visits. The benefit can last even after stopping the medicine.
  
  
• How long does it take to see results?
  While most people start to see a reduction in bleeding episodes within the first year of thalidomide, some patients may only see benefits after years of treatment and may require a prolonged course of thalidomide. It is important to use it safely and follow all instructions from your doctor.
  
  
• What blood tests and monitoring are needed before and during thalidomide treatment?
  Before starting thalidomide, doctors will order blood tests to check:
  
  • Full blood counts (FBC): To evaluate for low white or red blood cells, or platelets, since thalidomide can affect these.
  • Liver and kidney function tests: To make sure your liver and kidneys are healthy enough for treatment.
  • Screening for risk of blood clots: If you have a history of blood clots or inherited thrombophilia (e.g. protein C or protein S deficiency or antiphospholipid syndrome), extra precautions may be needed.
  • Pregnancy test: For women who could become pregnant, a negative pregnancy test is required before starting and regularly during treatment.
  • Neurologic exam: To check for any signs of nerve problems before starting.
    
    
  While taking thalidomide, these tests will be repeated regularly – often every month or as your doctor recommends – to monitor for side effects and ensure the medicine is safe for you. Blood counts, liver and kidney function, and pregnancy tests (for women of childbearing potential) are checked regularly. Your doctor will also ask about symptoms of nerve problems and may do neurologic exams during treatment.
  
  
• What are the risks and side effects?
  Common side effects include tiredness, constipation, sleepiness, and mild numbness or tingling in the hands or feet. Serious side effects can include nerve damage (peripheral neuropathy), blood clots, and severe birth defects if taken during pregnancy. Your doctor may recommend taking aspirin (or other blood thinners) with thalidomide to reduce the risk of blood clots. Thalidomide must never be used in pregnancy, and strict birth control is required for women who could become pregnant.
  
  
• Monitoring and safety
  Regular check-ups and blood tests are needed to watch for side effects. You should inform your doctor if you notice numbness, tingling, weakness or constipation.
  
  
• Other treatment options
  Treatment for vascular anomalies may also include observation, sclerotherapy, embolisation or surgery. Thalidomide or other targeted therapies are often considered when these options are not sufficient or not possible.

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