Methotrexate

Question 1

Which drugs have interactions with Methotrexate and need to be checked prior to commencing?

Answer 1

• Trimethoprim (Abx - ↑ risk of side effects: myelosuppresion + nephrotoxicity)
• Co-trimoxazole (Trimethoprim + sulfamethoxazole)
• Nitrous oxide (↑ risk of methotrexate toxicity)
• Acitretin (retinoid usesd for psoriasis - ↑ concentration of methotrexate)
• Clozapine (atypical antipsychotic - ↑ risk of myelosupression)
• Levetiracetam (anti-epileptic - ↓ clearance of methotrexate = toxicity)

Question 2

What stages should you go through for ANY drug counselling discussion?

Answer 2

1. Explain what you are going to talk about i.e. the following:
   
   • Make sure to check patient is following you, any questions so far?
2. What do you understand about the medication at the moment?
3. What the drug is for (benefits of action)
4. How does the drug work?
5. Mention leaflets + website for info after this session
6. How do you take the drug?
   
   • Form + quantity
   • How often?
   • Time of day?
   • For how long?
7. Does the drug require monitoring? - patient’s want to know frequency of blood tests
8. Side effects –> what signs to look for –> what to do in response
9. Restrictions / precautions for taking drug e.g. alcohol, certain foods

Question 3

How long will methotrexate take to start working?

Answer 3

Not straight away!

Often takes 3-12 weeks to feel a benefit

Question 4

How does methotrexate affect alcohol?

Answer 4

Keep to minimum, < 7 units per week

Question 5

Is there anything I need to have done if I am taking methotrexate?

Answer 5

Pneumococcal vaccine

Annual flu vacine

Both VERY important

Question 6

How is methotrexate monitored?

Answer 6

Blood monitoring required:

• Every 2 WEEKS until on a stable dose (consistent bloodwork) for 6 weeks
• Then EVERY MONTH for 3 months (provided dose is stable and bloodwork is satisfactory)
• Then ever TWO MONTHS thereafter

Question 7

Does methotrexate increase the risk of specific conditions?

Answer 7

Yes

Small increase in risk of Lymphoma / skin cancer

Question 8

What common side effects might a patient on methotrexate experience?

Answer 8

• Nausea / vomiting
• Diarrhoea
• Mouth ulcers
• Hair loss (often minor)
• Skin rashes

Question 9

What serious side effects can methotrexate have and what should patients do if they experience any?

Answer 9

Serious side effects - Report immediatly at onset of the following:

• Blood disorders (e.g. sore throat, bleeding, abnormal bruising)
• Liver toxicity (e.g. nausea, vomiting, abdominal discomfort, dark urine)
• Respiratory effects (e.g. SoB)

Question 10

What special counselling should be given to women taking methotrexate?

Answer 10

• If female of child-bearing age –> ask if planning on getting pregnant
• Methotrexate must be stopped 3/12 months in advance of trying for pregnancy
• Methotrexate = not compatible with breastfeeding

Question 11

Who should patients on methotrexate tell about their medication?

Answer 11

Inform any other prescribers that you are taking methotrexate!

Report it during any hospital admission

Question 12

Can I take pain killers if on methotrexate?

Answer 12

DO NOT buy NSAIDs - only take if prescribed + monitored

Question 13

How should I take methotrexate?

Answer 13

Dose is to be taken ONCE WEEKLY!

Swallowed whole - not halved, crushed or chewed

Question 14

Is there any other medication I need to take alongside methotrexate?

Answer 14

Folic acid

5mg weekly - usually 3 days after methotrexate (a non-methotrexate day)

Question 15

Are there any other conditions I should look out for?

Answer 15

Chicken pox OR shingles

• If you come into skin contact with someone with chicken pox or shingles, or develop chicken pox or shingles YOU MUST contact your GP or rheumatology department

Question 16

Provide a review of info that you need to tell a patient for methotrexate.

Answer 16

• How does it work?
  
  • Methotrexate is a type of ‘disease modifying antirheumatic drug, which suppresses your immune system, but no so much that it doesn’t function normally e.g. to fight infections
  • It should reduce pain, swelling and tenderness in your joints
  • Won’t feel benefit for 3-12 weeks
• How to take medication:
  
  • Taken as a tablet
  • Dose ONCE WEEKLY
  • Take FOLIC ACID 3/4 days after methotrexate dose
• Blood monitoring:
  
  • Every 2 weeks until stable for 6 weeks
  • Then every month for 3 months
  • Then every 2 months
  • We will give you a little book, in which we record the results
• Actions to take:
  
  • Pneumcoccal vaccine
  • Annual flu vaccine
• What to avoid:
  
  • Avoid alcohol (< 7 units p/w)
  • Avoid people with chicken pox or shingles - if contact or you develop these –> contact GP / rheumatology
  • NSAIDs (unless prescribed)
  • Smoking cessation
• Side-effects:
  
  • Common: nausea, vomiting, diarrhoea, mouth ulcers, hair loss (minor), skin rashes –> if bothering, let us know
  • Serious: blood disorder (bleeding or bruising), liver toxicity (nausea, vomiting, abdominal pain, dark urine, jaundice) or resp issues (SoB) –> tell GP or rheum when you notice symptom
  • Slight increase risk of lymphoma / skin cancer
• Women:
  
  • Stop 3/12 months before conception
  • Can’t have if breastfeeding