Antineutrophilics

Question 1

List the indications for dapsone?

Answer 1

Dermatitis herpetiformis
Leprosy

Immunobullous disease
Neutrophilic dermatoses
Erythema nodosum
AICTD
Vasculitis

Question 2

What are the contraindications to dapsone?

Answer 2

Hypersensitivity/allergy to sulfonamides
Pregnancy/lactation
G6PD deficiency
Peripheral neuropathy
Anaemia
Severe hepatic, renal or cardiopulmonary disease

Question 3

What are the adverse effects of dapsone?

Answer 3

Dapsone hypersensitivity (HLA B13:01)
Haemolytic anaemia, methaemoglobinaemia, agranulocytosis
Peripheral neuropathy
Psychosis
GI effects, transaminitis, cholestasis, pancreatitis

Question 4

What are the drug interactions to dapsone?

Answer 4

CYP3A4 drugs
Other folic acid antagonists
Hydroxychloroquine (peripheral neuropathy)
Local anesthetic (methaemoglobinemia)

Question 5

What is the baseline and ongoing monitoring for dapsone?

Answer 5

Baseline
FBC, UEC, LFT, BhCG, G6PD

Ongoing
FBC + retic weekly for 1 month, fortnightly for 2 months, and then every 3 months
UEC, LFT monthly for 2 months, and then every 3 months

Question 6

What are the indications for colchicine?

Answer 6

Familial Mediterranean fever
Neutrophilic dermatoses
Immunobullous disease
Leukocytoclastic vasculitis
CSU/Urticarial vasculitis

Question 7

What are the contraindications to colchicine?

Answer 7

Hypersensitivity
Pregnancy/lactation
Blood dyscrasias/BM suppression
Children <2 years
Severe hepatic, renal or cardiac disease

Question 8

What are the drug interactions to colchicine?

Answer 8

CYP3A4 drugs
NSAIDs
Alcohol
Statins

Question 9

What are the adverse effects of colchicine?

Answer 9

GI effects
Haem: cytopaenias, DIC
Renal: hyponaturemia, hypokalemia, renal failure
Other: liver failure, heart failure, oligospermia, ARDS
Alopecia

Question 10

How is colchicine dosed?

Answer 10

Start on 500mcg once daily
And increase to BD and then TDS

Question 11

What baseline and ongoing monitoring is required for colchicine?

Answer 11

Baseline
FBC, UEC, LFT, urinalysis, BhCG

Ongoing
FBC, UEC, LFT, urinalysis
Monthly for 3 months, then every 3 months

Question 12

What are the indications for potassium iodide?

Answer 12

Panniculitis
Neutrophilic dermatoses
Sporotrichosis
Wegeners granulomatosis
Granuloma annulare

Question 13

What are the contraindications to potassium iodide?

Answer 13

Hypersensitivity
Pregnancy/lactation
Thyroid disease
Hyperkalemia
Severe renal or cardiac disease

Question 14

What drugs interact with potassium iodide?

Answer 14

Lithium, amiodarone (thyroid)
Spironolactone, ACEi/ARB (hyperkalemia)

Question 15

What are the adverse effects of potassium iodide?

Answer 15

GI effects eg. dysgeusia, hypersalivation, burning mouth
URTI sx
Cytopaenias
Hyperkalemia
Hypothyroidism
CNS: headache, depression
Iododerma/halogenoderma

Question 16

How is potassium iodide formulated and dosed?

Answer 16

Supersaturated solution in orange juice = 1000mg/ml

Dropper holds 0.3ml/10 drops = 300mg

Start at 5 drops (150mg) and increase to 10 drops (300mg) tds

Question 17

What baseline and ongoing monitoring is required for potassium iodide?

Answer 17

Baseline
FBC, UEC, LFT, TFT, BhCG

Ongoing
FBC, UEC, TFT fortnightly for 1 month and then every 3 months

Question 18

True or false re Colchicine
A. Narrow therapeutic range
B. Most experience GI effects
C. Bioavailability highly variable
D. Can be used in children

Answer 18

All true