Methotrexate

Question 1

Indications of methotrexate

Answer 1

Moderate to severe active rheumatoid arthritis
Chron’s disease
Malignant disease
Psoriasis

Question 2

Monitoring parameters of methotrexate

Answer 2

• FBC, RFTs and LFTs before starting treatment, then weekly until stabilised and every 2-3 months thereafter due to blood dyscrasias and liver cirrhosis.
• Patients should be advised to report all symptoms and signs suggestive of infection, especially sore throat.

Question 3

Methotrexate dosing

Answer 3

• Weekly dose
• For moderate to severe rheumatoid arthritis 7.5mg once weekly
• Max weekly dose 20mg
• Only one strength of methotrexate tablet is prescribed and dispensed (2.5mg)

Question 4

Red flag symptoms

Answer 4

• Blood disorders = sore throat, bruising and mouth ulcers
• Liver toxicity = nausea, vomiting, abdominal discomfort and dark urine
• Respiratory effects = shortness of breath

Question 5

Gastrointestinal or myelosuppression side effects with methotrexate

Answer 5

Take 5mg of folic acid every week 24hours after methotrexate to reduce frequency of side effects.

Question 6

Methotrexate and aspirin

Answer 6

Increases methotrexate toxicity by reducing excretion of methotrexate

Question 7

Methotrexate and NSAID’s

Answer 7

Reduced methotrexate excretion leads to an increased risk of toxicity