Rheumatoid arthritis Flashcards
Symptoms
- Joint pain
- Swollen, heat, stiff + motion loss
- Rheumatic nodules
- Affects hands + feet
Drugs
Affects immune response
- Methotrexate
- Azathioprine
- Ciclopsorin
- Cyclophosphomide (hemorrhagic cystitis + permanent male sterility)
- Leflunomide (hepatotoxicity; effective contraception after treatment: M: 3M + F: 2Y)
Antimalarial
- Hydroxychloroquine
- Chloroquine (retinopathy; screen for ocular toxicity)
Cytokine modulator
- Rituximab
Treatment
Short term bridging treatment/flare up: corticosteroid OR NSAID
First line
Conventional DMARD (can take 2-3M to work)
- Methotrexate
- Leflunomide
- Sulfasalazine
- Hydroxychloroquine (Mild RA)
Treatment: severe active RA
Methotrexate + rituximab
MTX: MOA
blocks dihydrofolate reductase which is essential for making purines + pyrimidines tf cell replication
MTX: indication
- RA
- Crohn’s disease
- Psoriasis
- Cancer
MTX: dose
Once weekly
- Missed dose: >3 days
- MHRA: once weekly for autoimmune diseases: new measures
- Prescription: dose, freq + specific day
- Dispensing: specific day on outer packaging
- Counsel: do not take daily - fatal, report OD
- Folinic acid: reverse acute toxicity
Folic acid: dose
Possible regimens:
- 5mg once weekly different to MTX dose
- 1mg or 5mg OD except MTX day
MTX: side effect
Blood disorders
- Monitor: FBC
- CI: active infection, immunodeficiency syndromes
- Counsel: report signs of infection or blood disorders (fever, mouth ulcers, sore throat, bleeding or bruising
Nephrotoxicity
- RED dose in RI
- Monitor: RFT
- Caution: dehydration
Hepatotoxicity
- Monitor: LFT
- CI: ascites
Pulmonary toxicity
- CI: significant pleural effusion
- Counsel: report respiratory effects (dyspnoea, cough)
GI toxicity
- STOP if stomatitis or diarrhoea
- Caution: ulcerative stomatitis, peptic ulcers, UC
Phototoxicity
- MHRA: Methotrexate: phototoxicity
- Counsel: avoid UV light (inc sunlight btw 11am-3pm) wear high factor broad spec sunscreen + protective clothing
MTX: pregnancy
Teratogenic
- Effective contraception during + 6M after: men + women
MTX: handling
- Avoid skin contact w cytotoxic drugs - wear gloves
- Avoid in pregnant/breastfeeding women
MTX: interaction
Trimethoprim, phenytoin, clozapine → blood disorders
NSAID (vasoconstriction of afferent renal arteriole) → RED renal clearance = MTX toxicity
- Counsel: avoid OTC
Penicillin abx/PPI → RED renal clearance = MTX toxicity
Nephrotoxicity
- Gentamicin
- Cephalosporin
- NSAID
Hepatotoxic
- Co-amox + Flucox
- Tetracycline
- Carbamazepine + valproate
- Fluconazole
