Drugz Flashcards
Anti-inflamm and pain relief drugs for rheumatoid conditions
- Aspirin for transient MSK pain and pyrexia (fever)
- NSAIDs for inflam cond’s
- Paracetamol 1st line pain relief where NSAIDs not indicated. Codeine if not sufficient
Paracetamol (acetaminophen) mechanism of action
- Inhibits synthesis of prostaglandins in the CNS and peripherally blocks pain impulse generation
- Reduces pyrexia by inhibition of the hypothalamic heat-regulating centre
Paracetamol indications
Mild to moderate pain, pyrexia. NSAIDs are preferred for pain relief in the inflammatory arthritides
Paracetamol SEs
Rare unless in overdose
Paracetamol cautions/contraindications
Dosing interval 6 hours or greater if eGFR
NSAIDs mechanism of action
Inhibition of cyclo-oxygenase (COX), the enzyme which catalyses the synthesis of cyclic endoperoxidases from arachidonic acid to form prostaglandins.
Drawback of NSAID mechanism of action and how can it be avoided
- Inhibition of the COX-1 isoform in the GI tract leads to reduction in protective prostaglandins and predisposes to gastroduodenal damage.
- COX 2 is the form mainly induced in response to pro-inflammatory cytokines.
- The selective inhibitors of COX-2 (‘coxibs’, etoricoxib and celecoxib) have a lower risk of gastroduodenal damage that the non-selective NSAIDs (e.g. ibuprofen, diclofenac)
NSAIDs indications
- Pain and inflammation associated with inflammatory arthritides and severe osteoarthritis
- Crystal synovitis
- Transient MSK pain
- Pain caused by secondary bone tumours
E.gs of NSAIDs and their benefits and drawbacks
Ibuprofen - fewer SEs but anti-inflam weaker
Indometacin - more potent but more SEs
Diclofenac and naproxen in between the two
SE’s NSAIDs
- GI toxicity w highest risk in elderly. Inflammation and ulceration most apparent in stomach and duodenum
- Co-prescribe PPIs w non-selective NSAIDs in high risk pts (>65y, pmhx peptic ulceration, other med that inc GI risk: warfarin, aspirin, corticosteroids)
- Hypersensitivity reactions, blood disorders, fluid retention, AKI, hepatitis, pancreatitis, exacerbation of colitis
Cautions and contraindications NSAIDs
- contraindicated in pts w hx of hypersensitivity to aspirin or any other NSAID.
- contraindicated in severe HF
- Avoid in pts w previous GI ulceration
- In pts w renal, cardiac or hepatic impairment NSAIDs may cause a deterioration in organ function
What drugs affect bone metabolism?
bisphosphonates, calcium, vitamin D
mechanism of action bisphosphonates
adsorbed onto hydroxyapatite crystals in bone and inhibit growth and activity of osteoclasts, thereby reducing the rate of bone turnover
indications bisphosphonates
OSTEOPOROSIS -Prophylaxis and treatment in combination with calcium and vit D supplements if dietary intake inadequate.
PAGET’S DISEASE AND HYPERCALCAEMIA OF MALIGNANCY - treatment
OSTEOLYTIC LESIONS AND BONE PAIN in bone metastases associated with breast cancer or multiple myeloma - treatment
SE’s bisphosphonates
- GI - dyspepsia, nausea, vomiting, abdo pain, diarrhoea, constipation
- Flu like symptoms
- Oesophageal reactions with alendronic acid
- MSK pain
- Biochemical abnormalities (hypophosphataemia, hypocalcaemia, hyper or hypokalaemia, hypernatraemia)
- Anaemia
- Thrombocytopenia
- Lymphocytopenia
- Seizures
- AKI
- Conjunctivitis
- Osteonecrosis of the jaw - greatest risk in pts recieving IV bisphosphonates for cancer indications
Egs of bisphosphonates
Alendronic acid
Risedronate
Disodium pamidronate
Cautions / contraindications bisphosphonates
- correct vit D deficiency and hypocalcaemia before starting
- avoid risedronate and alendronate in symptomatic oesophageal disorders
- dose adjustment in severe renal impairment
what is the reference nutrient intake of calcium
700mg
indications for calcium
hypocalcaemia, osteomalacia, when dietary calcium intake (with or without vit D) is deficient in the prevention and treatment of osteoporosis
what preparations are used for calcium administration
calcium carbonate and calcium gluconate
SEs calcium
GI disturbances; with injection, peripheral vasodilatation, fall in blood pressure, injection-site reactions
vit D mechanism of action
fat soluble vitamin whose main action is to promote intestinal absorption of calcium. An oral supplement of 10µg prevents deficiency
vit D indications
- prevention in those at risk of deficiency e.g asians consuming unleavened bread and in the elderly
- adjunct in osteoporosis rx
- vit D def caused by intestinal malabsorption, chronic liver dis and severe renal impairment
- hypocalcaemia and hypoparathyroidism
preparations of vit D?
ergocalciferol
alfacalcidol
calcitriol
