Gout

Question 1

Allopurinol MOA and counselling points

Answer 1

Xanthine oxidase inhibitor- reduces production of uric acid, lowers serum urate concentration
Wait until an attack has settled prior to starting allopurinol therapy
Side effects include oedema, rash, raised liver enzymes, SJS hypersensitvity (rare but serious)- rash, swollen lips or mouth, persistent fever or sore throat
Take with or shortly after food to reduce stomach upset
May get more frequent flares in the first few months of taking it- doesn’t mean the treatment isn’t working. Once urate crystal levels are low enough in the body, gradually flares will improve and eventually stop
See doctor for regular tests

Question 2

Febuxostat MOA and counselling points

Answer 2

Xanthine Oxidase Inhibitor- reduces serum urate concentration and inhibits uric acid production
As with allopurinol, more flares at first, raised liver enzymes, oedema, rash, SJS (swelling of lips or mouth, persistent fever or cough, rash)
May make you feel dizzy or drowsy
See doctor for monitoring of urate levels, kidney and liver function tests

Question 3

Colchicine MOA and counselling points

Answer 3

MOA: reduces inflammation, inhibits inflammatory response in inflamed tissue (i.e. neutrophil migration, chemotaxis, adhesion, phagocytosis)
Used when experiencing an acute flare
Do not take more than 3 tablets in a course or repeat the course within 3 days
CYP- avoid grapefruit
Stop taking if you develop severe diarrhoea, vomiting, muscle pain, tenderness or weakness, numbness or tingling in your fingers or toes, unusual bleeding or bruising, or signs of infection
Needs frequent blood tests (at month 1, 6, then annually)

Question 4

Probenecid MOA and counselling points

Answer 4

Increases renal excretion of uric acid by blocking renal tubular reabsorption.
Reduces renal tubular excretion of some drugs, increasing their conc and prolonging duration of action.
Side effects include rash, nausea, vomiting, headache, dizziness, SJS (rare)
Take with food to minimise GI upset, drink lots of fluid during treatment to prevent kidney stones
Will get more flares in the first few months
Regular blood tests- see doctor