Musculoskeletal system

Question 1

Allopurinol

Answer 1

Allopurinol = xanthine oxidase inhibitor. Xanthine oxidase metabolise xanthine to uric acid. Inhibitor reduces level of uric acid
✖During acute gout attacks
✖Recurrrent skin rash
✖Severe hypersensitivity

Prevent recurrent attacks of gout
Prevent uric acid and oxalate renal stones
Prevent hyperuricaemia and tumour lysis syndrome during chemotherapy

Question 2

Methotrexate

Answer 2

Inhibits dihydrofolate reductase involved in converting dietary folic acid to tetrahydrofolate (FH4). FH4 needed in DNA replication especially in dividing cell such as cancer. Methotrexate also has anti-inflammatroy effects, mechanism of which unclear
✖Pregnancy
✖Severe renal impairment

Rheumatoid arthritis
Part of chemotherapy regimen
Treatment of severe psoriasis

Question 3

(Non-steroidal anti-inflammatory drugs)

Answer 3

Inhibits prostaglandin synthesis from arachidonic acid via inhibition of cyclo-oxygenase (COX) pathway. COX has 2 isoforms: COX-1 (stimulates prostaglandin synthesis needed in gastric mucosa integrity, renal perfusion and inhibiting thrombus formation) + COX-2 (causing inflammation and pain). COX-2 inhibition associated with therapeutic effect and COX-1 inhibition with adverse. 
✖Severe renal impairment 
✖Heart failure 
✖Liver failure 
✖NSAID insensitivity

Question 4

Naproxen

Answer 4

(Non-steroidal anti-inflammatory drugs)

Treatment of mild to moderate pain
Pain related to inflammation

Question 5

Ibuprofen

Answer 5

(Non-steroidal anti-inflammatory drugs)

Treatment of mild to moderate pain
Pain related to inflammation

Question 6

Etoricoxib

Answer 6

(Non-steroidal anti-inflammatory drugs)

Treatment of mild to moderate pain
Pain related to inflammation

Question 7

Paracetamol

Answer 7

Weak inhibitor of cyclo-oxygenase (COX), specifically COX-2

Acute and chronic pain
Fever