Anti-Arthritic drugs

Question 1

types and causes of arthritic disorders

Answer 1

1. osteoarthritis
   - caused by inflammation to the cartilage, causing degeneration
2. gouty arthritis
   - caused by increase in systemic uric level, causing build up as gouty nodules
3. rheumatoid arthritis
   - caused by autoimmune disease that targets the synovium/bones

Question 2

treatment for osteoarthritis

Answer 2

1. pain relieving
   - NSAIDs/corticosteroids
2. viscosupplementation
   - intra-articular hyaluronic acid

Question 3

function of NSAIDs/corticosteroids in OA

Answer 3

anti-inflammatory, pain relieving

Question 4

function of viscosupplementation in OA

Answer 4

intra-articular hyaluronic acid is to provide shock absorption, lubrication and also to increase synthesis of biological hyaluronic acid

Question 5

treatment for gouty arthritis

Answer 5

1. pain relief and anti-inflammatory
   - NSAIDs, corticosteroids, colchicine
2. anti-hyperuricemic drugs
   - allopurinol and probenecid

Question 6

colchicine (indications, MOA, side effects)

Answer 6

Indications: used as pain relief in gouty arthritis

MOA: binds to tubulin, decreases polymerisation of microtubules and thus inhibits leukocyte migration and the subsequent leukotriene/prostaglandin production = cannot stimulate pain receptors

side effects: hepatotoxic

Question 7

allopurinol (indications, MOA, side effects)

Answer 7

Indications: used as anti-hyperuricemic drug in gouty arthritis

MOA: xanthine oxidase inhibitor; decreases uric acid production from purines

Side effect: dark urine / renal toxicity

Question 8

probenecid (indications, MOA, side effects)

Answer 8

Indications: used as anti-hyperuricemic drug in gouty arthritis; only when allopurinol does not work or if the gout is rapidly worsening

MOA: uricosuric agent; increases uric acid excretion

Side effects: renal toxicity

Question 9

treatment of rheumatic arthritis

Answer 9

1. anti-inflammatory
   - NSAIDs, glucocorticoids
2. synthetic DMARD (disease modifying anti-rheumatic drug)
   - methotrexate, hydroxychloroquine, cyclosporin A, tofacitinib
3. biological DMARD
   - anti-TNFa monoclonal antibodies, recombinant IL-1R antagonist, anti-IL6R monoclonal antibodies

Question 10

name all 4 synthetic DMARDs

Answer 10

methotrexate, hydroxychloroquine, cyclosporin A, tofacitinib

Question 11

name all 3 drug classes of biological DMARDs and their examples

Answer 11

anti-TNFa mAb = adalimumab, etanercept, infliximab

anti-IL6R mAb = tocilizumab

recombinant IL-1R antagonist = anakinra

Question 12

methotrexate (drug class, MOA, side effects)

Answer 12

Drug class: synthetic DMARD

MOA: folic acid analogue - decreases folic acid synthesis = decreases DNA synthesis for T cell proliferation and thus down regulates immune response

Side effects: renal impairment

Note: is also used as an anti-cancer drug

Question 13

hydroxychloroquine (drug class, MOA)

Answer 13

Drug class: synthetic DMARD

MOA: reduces MHC II expression - less antigen presentation

Question 14

cyclosporin A (drug class, MOA)

Answer 14

Drug class: synthetic DMARD (but also an immunosuppressant)

MOA: reduces cytokine gene transcription and T cell proliferation

Question 15

tofacitinib (drug class, MOA)

Answer 15

Drug class: synthetic DMARD

MOA: Janus kinase inhibitor - prevents gene transcription

Question 16

adalimumab, etanercept, infliximab (drug class, MOA)

Answer 16

Drug class: anti-TNFa mAb

MOA: binds to TNFa which is an inflammatory cytokine

Question 17

tocilizumab (drug class, MOA)

Answer 17

Drug class: anti-IL6R mAb

MOA: prevents binding of IL-6 to its receptor

Question 18

anakinra (drug class, MOA)

Answer 18

Drug class: recombinant IL-1R mAb

MOA: binds to IL-1R and blocks signalling

Question 19

indications of biological DMARDs

Answer 19

used if synthetic DMARD is not working well

Question 20

contraindications of biological DMARDs

Answer 20

avoid in patients with infection - hep B or TB because you don’t want to suppress their immunity/inflammation