methotrexate + hydroxychloroquine Flashcards
(13 cards)
methotrexate mode of action
antimetabolite that inhibits dihydrofolate reductase
(an enzye vital for synthesis of purines + pyrimidines)
indications for methotrexate
inflmmatory arthritis - esp RA
psoriasis
some chemo acute lymphoblastic leukaemia
side effects of methotrexate
myelosuppression
pneumonitis
pulmonary fibrosis
liver fibrosis
mucositis
most common pulmonary manifestation of methotrexate effect
pneumonitis
- similar disease pattern to hypersensitivity pneumonitis secondary to inhaled organic antigens
typically develops within a year of starting tx
px = non-productive cough, dyspnoea, fever, malaise
methotrexate and pregnancy
avoid pregnancy for at least 6 months after tx has stopped
MEN TOO !! use contraception for 6 months after tx
how often would a dose of methotrexate taken
weekly, not daily
what needs to be monitored in patients taking methotrexate
FBC
U&E
LFTs
- monitored weekly until stabilised
- then every 2-3months
what drug should be co prescribed with methotrexate? why is it needed?
folic acid 5 mg once weekly
- take more than 24hrs after methotrex dose
reduces risk of myelosuppression
drug interactions with methotrexate
trimethoprim or co-trimoxazole !!
–> increase risk of marrow aplasia
high dose aspirin
–> increases risk of methotrexate toxicity secondary to reduced excretion
treatment of methotrexate toxicity
folinic acid
key side effect of hydroxychloroquine
bulls eye retinopathy
- may result in severe + permanent visual loss
what annual screening should be done in those taking hydroxychloroquine
baseline ophthalmological examination
can hydroxychloroquine be used in pregnancy
yes !
