Pharmacotherapeutic of gout

1. GOUT
(Pharmacology and therapeutics)
Pawan maharjan

2. Introduction
• Gout is disorder of purine metabolism in which the blood
uric acid level is raised either due to over production or
impaired excretion.
• Normal plasma uric acid 3.4–7.2 mg/dl for men and for
female 2.4–6.1 mg/ dl).
• Uric acid, a product of purine metabolism, has low water
solubility, especially at low pH.
• When blood uric acid levels are high, it precipitates and
deposits in joints, kidney and subcutaneous tissue as
sodium urate, which causes pain and inflammation of such
parts.
• If not treated, it might cause permanent deformities of
joint aswell.

3. Etiology
• Hyperuricaemia
• Reason for hyperuricemia
– Consumption of high purine diet
– Impaired in excretion due to kidney disease
– Degradation of muscle
– Drug induced: Frusemide, levodopa, thiazide
– Obesity

4. TYPES OF GOUT
• Primary gout: It is usually due overproduction or under
excretion without any other secondary cause or disease
condition.
• Secondary gout: It occur due secondary disease or due to
use of medicines
a) Leukaemias, lymphomas, polycythaemia especially
when treated with chemotherapy or radiation: due to
enhanced nucleic acid metabolism and uric acid
production.
(b) Drug induced-thiazides, furosemide, pyrazinamide,
ethambutol, levodopa, reduce uric acid excretion by kidney

5. Types of gout according to onset
Acute Gout: Chronic Gout

6. Chronic gout
In chronic case tophi
(chalk-like Stones under
the skin in pinna, eyelids,
nose, joints and other
places) and urate stone in
kidney.
Chronic gouty arthritis
may cause progressive
disability and permanent
deformities.

7. Pathogenesis of Gout

9. Clinical features
Swollen and Inflammation of joint,
mainly monoarticular.
Intense pain and tender in joint
• Primarily affect metatarso
phalangeal joint of big toe
• Limited range of movement
• Crystal deposit on pinna, elbow,
knees
• Formation of Tophy
• Gouty nephrolithiasis/nephropathy

10. Non pharmacological
• Avoid Purine containing food: Red meat, beer
• Avoid Junk food.
• Daily exercise
• Weight management
• Stress management

11. Pharmacological managment
Classification of medicines
1) Acute attack of gout:
– NSAIDs
– Colchicine
– Corticosteroids
2) For chronic gout and long term control.
– Uricosurics: Probenecid, Sulfinpyrazone
– Synthesis inhibitor: Allopurinol, Febuxostat

12. Medicine for acute attack
NSAID: Indomethacin, Diclofenac, naproxen, aceclofenac etc.
• But Aspirin is not used as it might decrease excretion of uric acid
Corticosteroid: Prednisolone, methylprednisolone,
• They are used due to strong anti-inflammatory and analgesic property.
• They are not recommended for long term use due to toxicity
Colchine: Dose: 0.25-1 mg
• It is an alkaloid derived from Colchicum autumnale.
• Colchicine does not have analgesic nor anti inflammatory as NSAID but
it specifically suppresses gouty inflammation.
• Chronic therapy might cause: aplastic anemia, agranulocytosis, hair
loss , myopathy, oligospermia, Azospermia
• Other: G.I irritation
•

13. Medicine for chronic use
Uricosuric agent:
• Probencid, Sulfinpyrazone
• These are the medicine which decrease the
uric acid by increasing its excretion.
• Dose of probencid: Dose: 0.25 gm- 0.5 gm
twice daily.

14. Uricosuric agent
• Adverse effects of probencid :
• Probenecid is generally well tolerated.
• Dyspepsia/indigestion t (up to 25% incidence with high
doses).
• It should be used cautiously in peptic ulcer patients.
• Rashes and other hypersensitivity phenomena are rare.
• Toxic doses cause convulsions and respiratory failure

15. Uricosuric agent
• Sulfinpyrazone.
• Pharmacological action is similar to probencid
• Pharmacokinetics:
• It is well absorbed orally and 98% plasma protein
bound.
• Excretion is fairly rapid, mainly by active secretion in
proximal tubule
• Dose: 100-200mg od/bd
• Adverse effects : Gastric irritation is most common so
contraindicated in peptic ulcer.
• Rarely: hypersensitivity reaction.

16. Uric acid synthesis inhibitors; Allopurinol
and febuxostat
These drug inhibit synthesis of uric acid.
Allopurinol:
Dose: Start with 100 mg OD,
gradually increase to maintenance
dose of 300 mg/day; maximum 600
mg/day
Adr: N/V, skin rashes
Febuxostat:
Dose: 40 mg/d - 80 mg/d; maximum
120 mg/d
Adverse effect:
Liver damage
Hypersensitivity reaction
Diarrhoea, nausea, headache
,Diet

17. Thank you