methotrexate

Question 1

what is methotrexate

Answer 1

low doses to treat inflammatory skin conditions such as psoriasis and eczema/dermatitis. It is also prescribed for rheumatoid arthritis, psoriatic arthritis, and increasingly, other inflammatory and autoimmune disorders (off-label). In much higher doses, it is used as a chemotherapy agent for leukaemia and some other forms of cancer.

Question 2

which skin diseases respond to methotrexate

Answer 2

moderate to severe psoriasis

• Atopic dermatitis
• Pityriasis rubra pilaris
• Pompholyx and other forms of chronic hand dermatitis
• Pityriasis lichenoides (PLC) and pityriasis lichenoides et varioliformis acuta (PLEVA)
• Chronic spontaneous urticaria
• Immunobullous diseases such as bullous pemphigoid and pemphigus
• Morphoea (localised scleroderma)
• Cutaneous lupus erythematosus

Question 3

How quickly does the skin condition improve on methotrexate?

Answer 3

within 6 to 8 weeks

maximum effects are generally achieved within 5-6 months

Question 4

how does methotrexate work

Answer 4

anti inflammatory properties
immune modulatory effects
antimetabolite - reduces skin

Question 5

contraindications to methorexate

Answer 5

pregnancy
breastfeeding
low blood counts - anaemia, leukopenia, thrombocytopenia
sever liver disease

Question 6

how does methotrexate affect pregnancy

Answer 6

miscarriage or stillnirth esp in the first 3 months of pregnancy

do not taks while being pregnant

childbearing age

Question 7

tests before starting methotrexate

Answer 7

FBC
kidney function - creatinine
LFTs
P3NP - hepatic fibrosis
HbA1c
hep B and C
HIV
Varicella

Question 8

SEs of methotrexate

Answer 8

loss of appetitie
nausea
diarrhoea
reduce folic acid
cirrhosis or fibrosis
pneumonia - chest xray

Question 9

drug interactions with methotrexate

Answer 9

trimethoprim or sulphonamides

aspirin or NSAID