Pharmacology of Arthritis

Question 1

What are the functions of NSAIDs?

Answer 1

Anti-inflammatory

Analgesic

Question 2

What are examples of NSAIDs?

Answer 2

Ibuprofen
Naproxen
Diclofenac
Indometacin
Etodolac

Question 3

What are indications for NSAID use?

Answer 3

Inflammatory arthritis
Mechanical MSK pain
Pleuritic/ pericardial pain

Question 4

What are some adverse effects of NSAIDs?

Answer 4

Dyspepsia
Oesophagitis
Gastritis
Peptic ulcer
Small/ large bowel ulceration 
Renal impairement
Increased CV events
Fluid retention
Wheeze
Rash

Question 5

When should a DMARD be used in inflammatory arthritis?

Answer 5

Within 3 months of symptom onset

Question 6

Are DMARDs slow or fast acting?

Answer 6

Slow acting - weeks to months

Question 7

What is the mode of DMARDs?

Answer 7

Pure anti-inflammatory with no direct analgesic effect

Modify the disease progression and reduce the rate of joint damage

Question 8

What are the commonly used DMARDs?

Answer 8

Methotrexate
Sulphasalazine
Leflunomide
Hydroxychloroquine

Question 9

What is the mode of action of methotrexate?

Answer 9

Folate antagonist

Question 10

How can DMARDs be administered?

Answer 10

Orally

Subcutaneous

Question 11

What is methotrexate used in?

Answer 11

RA
Psoriatic arthritis
CTD
Vasculitis

Question 12

What are the adverse effects to methotrexate?

Answer 12

Leucopenia/ thrombocytopenia
Hepatitis/ cirrhosis
Pneumonitis
Rash/ mouth ulcers
Nausea/ diarrhoea

Question 13

What blood tests are required for methotrexate use?

Answer 13

FBC

LFTs

Question 14

Can methotrexate be used in pregnancy?

Answer 14

No it is teratogenic

Must be stopped at least 3 months before conception in females AND males

Question 15

Describe leflunomide?

Answer 15

Simliar efficacy and side effects to methotrexate

Also teratogenic but has a very long half life to wash out is required

Question 16

When is sulfasalazine used?

Answer 16

Often used in combo with methotrexate in early inflammatory arthritis

Question 17

What are the adverse effects of DMARDs?

Answer 17

Nausea
Rash/ mouth ulcers
Neutropenia
Hepatitis
Reversible oligozoospermia

Question 18

What monitoring needs to be done for patients on sulfasalazine?

Answer 18

FBC

LFTs

Question 19

What is the function of hydroxycholorquine?

Answer 19

No effect on joint damage

Used in CTD for skin, fatigue and joint pain

Question 20

In what conditions is hydroxychloroquine used?

Answer 20

SLE
Sjogren’s
RA

Question 21

What is a rare but serious adverse effect of hydroxychloroquine?

Answer 21

Retinopathy

Question 22

What are biologics?

Answer 22

Drugs designed to target specific aspects of the immune system found to be implicated in inflammatory arthritis

Question 23

What are common targets of biologics?

Answer 23

TNF
CD20 B cells
IL-6
IL-17, 12 and 23

Question 24

What is anti-tnf therapy licensed for?

Answer 24

RA
Psoriatic arthritis
Ankylosing spondylitis

Question 25

How is anti-tnf therapy administered?

Answer 25

Subcutaneous injection

Question 26

What are examples of anti-tnf therapies?

Answer 26

Etancercept | Infliximab

Question 27

In RA, who will qualify for anti-TNF therapy?

Answer 27

High disease DS28 score - 5.1 or higher | Use of previous DMARDs

Question 28

What are adverse effects of anti-TNF therapy?

Answer 28

RIsk of TB (always check for latent TB) Increased risk of skin malignancy Contraindicted in pulmonary fibrosiis and heart failure

Question 29

What drugs are used for the acute treatment of gout?

Answer 29

Colchicine NSAIDs Steroids - oral or IM

Question 30

What is a common adverse effect of colchicine?

Answer 30

Diarrhoea

Question 31

What drugs can be used for gout prophylaxis?

Answer 31

Allopurinol Febuxostat Uricosurics

Question 32

What is the mode of action of allopurinol?

Answer 32

Xanthine oxidase inhibitor

Question 33

What are the adverse effects of allopurinol?

Answer 33

Rash (vasculitis) | Azathioprine interaction causing marrow aplasia

Question 34

What is the mode of action and indication for febuxostat?

Answer 34

Xanthine oxidase inhibitor | Used in those who cannot tolerate allopurinol and those with renal impairment

Question 35

What are the indications of corticosteroid use in rheumatology?

Answer 35

CTDs Polymyalgia rheumatica/ GCA Vasculitis RA

Question 36

How can corticosteroids be administered?

Answer 36

``` PO Intra-articular Soft tissue injections IM IV ```

Question 37

What are the adverse effects of corticosteroids?

Answer 37

``` Weight gain - centripetal Muscle wasting Skin atrophy Osteoporosis Diabetes Hypertension Cataract Glaucoma Fluid retention Adrenal suppression Immunosuppression AVN of femoral head ```

Question 38

How can you reduce corticosteroid toxicity?

Answer 38

Use lowest possible dose for as short a time as poss Consider steroid sparing agents Osteoporosis prophylaxis Watch CV risk