Week 3 - Methotrexate therapuetics

Question 1

What strength does methotrexate come in ?

Answer 1

2.5mg

Question 2

How often should methotrexate be taken?

Answer 2

once weekly

Question 3

Why is a low dose test dose required ?

Answer 3

to test for adverse effects

Question 4

In RA how long can it take for methotrexate to show some therapeutic effect?

Answer 4

6 weeks to show some therapeutic effect and then 12 weeks for optimal effect

Question 5

What is the dose escalation of methotrexate in RA and how frequent is the escalation ?

Answer 5

2.5mg to 5mg increases every 1-3 weeks

Question 6

Before starting therapy what baseline assessments are carried out?

Answer 6

• Full blood count (FBC) - WBC
• Liver function test (LFT)
• Urea and electrolytes (U&E)
• Renal function (creatinine, Cr or estimated glomerular filtration rate, eGFR)
• Chest x-ray

Question 7

What are some self monitoring that patients can do?

Answer 7

Signs of an infection, sore throat bleeding- blood disorder

Nausea , vomiting abdominal discomfort , dark urine - liver toxicity

SOB- respiratory effects

Question 8

What are the key side effects of methotrexate?

Answer 8

• GI toxicity
• Liver toxicity
• pulmonary constriction
• skin reactions

Question 9

What are key contraindication of methotrexate?

Answer 9

• Active infections
• severe renal impairment
• hepatic impairment
• pregnant / breast feeding

Question 10

Why is folic acid co-prescribed with methotrexate ?

Answer 10

To manage GI side effects and Hepatic toxicity

Question 11

How often should folic acid be taken?

Answer 11

everyday except the day methotrexate is to be taken

Question 12

What should happen if Methotrexate dose is missed ?

Answer 12

If the dose can be taken within two days of the regular day ( folic acid should NOT be taken on this day)

Question 13

What drug interactions are there with methotrexate?

Answer 13

• NSAID
• Ciclosporin
• Anti-folates - trimethoprim, co-trimoxazole
• Live vaccines