Rheum drugs Flashcards
which drug would you prescribe for treatment/prevention of osteoporosis?
ALENDRONIC ACID 10 mg OD or 70 mg once weekly
what is the MOA of alendronic acid?
Absorbed onto hydroxyapatite crystals in bone, slowing both their rate of growth and dissolution - reduced bone turnover.
name the characteristic ADRs of alendronic acid
- oesophageal ulcer or stenosis, oesophagitis
- atypical femoral fractures
- jaw osteonecrosis
- external auditory canal osteonecrosis
what recommendations would you give a pt prescribed alendronic acid?
- tablets should be swallowed whole with plenty of water whilst sitting/standing
- take on empty stomach at least 30 mins before breakfast (or another oral medicine) - should stand or sit upright for at least 30 mins after administration
- pt should report any thigh, hip or groin pain during treatment
- pts should stop taking tablets and seek medical attention if dev. symptoms of oesophageal irritation such as dysphagia, new or worsening heartburn, pain on swallowing or retrosternal pain
describe the MOA of methotrexate
antimetabolite that inhibits dihydrofolate reductase… inhibits purine and pyrimidine synthesis
name the common indications and doses for methotrexate
- RA
- moderate: 7.5 mg PO once weekly, adjust according to response, max 20 mg/week
- severe: initially 7.5 mg/week IM or SC, increase in steps of 2.5 mg/week, max 25 mg/week
- Severe Crohn’s disease
- inducing remission: 25 mg/week IM
- maintenance: 10-25 mg/week PO
- Neoplastic diseases
name characteristic ADRs of methotrexate
- mucositis
- myelosuppression - increased risk of infection
- pneumonitis and pulmonary fibrosis/ILD
- liver fibrosis
- nephrotoxicity
what recommendations would you give a pt prescribed methorexate?
- must be taken ONCE WEEKLY, on same day
- give folic acid 5 mg once weekly (taken >24 hrs after methotrexate dose) to reduce ADRs
- stop treatment if ulcerative stomatitis develops (may be 1st sign of GI toxicity)
- report immediately onset of any features of blood disorders (e.g. sore throat, bruising and mouth ulcers), liver toxicity (e.g. nausea, abdo discomfort and dark urine) and resp effects (e.g. SOB)
- effective contraception during and for at least 6 mths after treatment in men and women
which drugs should not be prescribed alongside methotrexate?
- trimethoprim or co-trimoxazole - increased risk BM suppression
- high-dose aspirin - increases risk of methotrexate toxicity
what is the main contraindication to methotrexate?
pregnancy
what is the MOA of hydroxychloroquine? Name 2 indications.
DMARD: inhibits dendritic cell TLR 9 (recognition of DNA-containing immune complexes)… decreased interferon release, decreased T-cell Ag presentation… decreased anti-DNA auto-inflammatory processes.
- SLE
- active RA
name a characteristic ADR of hydroxychloroquine.
Bull’s eye retinopathy - may result in severe and permanent visual loss.
which drug would you prescribe for remission maintenance in Crohn’s disease? What is its MOA? What do you need to measure before prescribing?
AZATHIOPRINE: converted to 6-mercaptopurine anti-metabolite and inhibits purine metabolism and DNA synthesis.
TPMT (metabolises 6-MP) genotyping/phenotyping must be performed before prescribing as low activity levels cause high risk of myelosuppression.
name ADRs of azathioprine
- myelosuppression
- hepatitis
- pancreatitis
- lymphoma and non-melanoma skin cancer
