Leflunomide therapeutics

Question 1

What are the side effects of Leflunomide?

Answer 1

Common:
- GI disturbances
- Alopecia
- Skin reactions
- Dizziness

Other key/important side effects:
- Hepatic impairment
- Bone marrow suppression- leucopenia, anaemia, thrombocytopenia, pancytopenia
- Increased BP (common)

Question 2

What needs to be monitored when taking leflunomide?

Answer 2

Throughout their treatment patients should be monitored to ensure patient safety.

• Liver function tests (LFTs)
• FBC (full blood count)
• BP
• This is done prior to treatment
• Every 2 weeks for the first 6 months
• Then, every 8 weeks

Question 3

What are the contraindications for taking Leflunomide?

Answer 3

1. Hepatic impairment - accumulation
2. Severe immunodeficiency
3. Severe infection
4. Severe hypoproteinaemia
5. Moderate to severe renal impairment - no data
6. Pregnancy
7. Breastfeeding

Question 4

What are the cautions for taking leflunomide?

Answer 4

• Administration with haemototoxic or hepatotoxic drugs
• History of TB
• Bone marrow suppression- anaemia, leucopenia, thrombocytopenia

Question 5

What is leflunomide?

Answer 5

• Leflunomide is a DMARD
• It is indicated for the treatment of RA

Dose in RA:
Oral 100mg OD for 3 days (loading dose)
Then DECREASE down to 10-20mg OD

• Giving a loading dose can increase the risk of adverse events and can be omitted

Time to take effect:
- As with other DMARD therapies, its time to take effect is not instant and the effect can take up to 4-6 weeks to have an effect and may further improve up to 4-6 months.
- Let the patient know and ensure they continue taking their medication

Question 6

How long is the half-life of the active metabolite of leflunomide?

Answer 6

The active metabolite of leflunomide has a long half life - 1-4 weeks

• Monitoring after discontinuation is required

Washout procedure (to remove active metabolite from system):
- Stop treatment
- Give colestyamine 8g TDS or activated charcoal 50g QDS
- Treat for 11 days

Question 7

What addition advice should be given to patients on Leflunomide?

Answer 7

• Avoid live vaccines
• Avoid alcohol (increases risk of hepatic impairment)
• Can be taken with our without food