Arthritis Flashcards
What is rheumatoid arthritis?
Autoimmune disease where the immune system mistakenly attacks the synovium
What are the symptoms of rheumatoid arthritis?
Joint pain and swelling, usually affects hands, feet and wrists
What is used to treat rheumatoid arthritis?
DMARDs
Disease modifying anti rheumatic drugs
What do you use to treat new diagnosis of rheumatoid arthritis?
Methotrexate + other DMARD + temporary corticosteroid
What are the DMARDs?
Sulfasalazine
Penicillamine
Gold
What are the side effects of the DMARDs?
Blood dyscrasias
Sulfasalazine colours secretions orange/yellow
What are the antimalarial DMARDs?
Hydroxychloroquine
Chloroquine
What screening needs to occur when using antimalarial DMARDS?
Ocular toxicity
What are the DMARDs that affect the immune response?
Methotrexate Azathioprine Ciclosporin Leflunomide Cyclophosphamide
What are the side effects of the DMARDs that affect the immune response?
Blood dyscrasias
Ciclosporin - hepatotoxic
Leflunomide - hepatotoxic (contraception 2 years after treatment for women, 3 months for men)
Cyclophosphamide- cytotoxic anthracycline, urothelial toxicity (haemorrhagic cystitis, permanent male sterility)
What are the cytokine modulating DMARDs?
Infliximab
Etanercept
What are the side effects of the cytokine modulating DMARDs?
Blood dyscrasias
Report symptoms of TB
What is the mechanism of action of methotrexate?
Anti folate
Inhibits the conversion of dihydrofolate to tetrahydrofolate needed to make purines and pyrimidines and therefore DNA - prevents cellular replication
Are antifolate drugs teratogenic?
Yes
Also cause blood dyscrasias
What is methotrexate used for?
Rheumatoid arthritis
Cancer
Psoriasis
Crohn’s
When is methotrexate taken?
Once weekly on the same day each week
What must be on a prescription for methotrexate?
Dose and frequency and only prescribe one strength
Why is folic acid taken with methotrexate?
Helps reduce methotrexate side effects
What are the regimens used for folic acid when taken with methotrexate?
5mg once weekly on day after methotrexate
5mg daily except on methotrexate day
1mg daily except methotrexate day
What do you do if you miss a dose of methotrexate?
> 3 days take next scheduled dose on normal day
What are the counselling points for methotrexate?
Weekly doses and avoid OTC NSAIDs
Annual flu vaccination
Methotrexate treatment booklet
What are the side effects of methotrexate?
Blood dyscrasias Hepatotoxicity Nephrotoxicity Pulmonary toxicity GI toxicity
What are the methotrexate counselling points for blood dyscrasias?
Low white blood cells - susceptible to infection. Report mouth ulcers, fever, malaise, sore throat
Low red blood cells - anaemia. Report extreme tiredness, pallor, dizziness
Low platelets - thrombocytopenia. Report bruising and bleeding easily
What are the methotrexate counselling points for hepatotoxicity?
Report nausea, vomiting, dark ursine, jaundice, abdominal pain, pruritis, malaise, pale coloured stools
What are the methotrexate counselling points for pulmonary toxicity?
Report shortness of breath, cough, fever
What are the methotrexate counselling points for GI toxicity?
Report stomatitis as its the first sign of GI toxicity
When does contraception need to be used with methotrexate?
During and 3 months after
What are the methotrexate interactions that cause an increased risk of blood disorders?
Phenytoin
Trimethoprim
Co-trimoxazole
Clozapine
What are the methotrexate interactions that cause reduced renal excretion and therefore methotrexate toxicity?
NSAIDs
What are the methotrexate interactions that cause an increased risk of hepatotoxicity?
Isotretinoin
Phenothiazines
Rifampicin
Ketoconazole
