Sulphonamide

Acetazolamide, Dorzolamide and Brinzolamide are sulfonamide derivatives which act by inhibiting carbonic anhydrase (carbonic anhydrase inhibitor). Being sulphonamide derivatives they are contraindicated in patients with allergy to sulphonamides.

Ref: Essentials of Pharmacology By K D Tripathi, 5th Edition, Pages 188, 553; Medicinal Chemistry By Sriram, Page 227.

• Barbiturate
• Chloramphenicol
• Sulfonamides
• Thiopental Na
• Oral contraceptives
• Phenylbutazone
• Rifampicin

Sulphonamides can precipitate kernicterus in the new born, especially if premature, by displacement of bilirubin from plasma protein binding sites and more permeable blood brain barrier.

Hence it may lead to unconjugated hyperbilirubinemia.

Free Bilirubin can become deposited in the basal ganglia and subthalamic nuclei of the brain, causing an encephalopathy called kernicterus.

Ref:D. A. Warrell, Timothy M. Cox, John D. Firth (2005), Chapter 7 “Infection”, In the book “Oxford Textbook of Medicine”, 4th Edition, New york, Volume 1, Page 737

Ans. is ‘c’ i.e., Zonisamide

o Zonisamide is a sulfonamide medication used for the treatment of seizures. It has been associated with severe skin reactions, those typically seen with sulfa reactions. This medication should not be used in sulfa-allergic patients.

Ans. is ‘b’ i.e., Sulfadoxine

Sulfadoxine and sulfamethopyrazine are long acting sulfonamides.

Ans. is ‘a’ i.e., Competitive inhibition

Bacteria synthesize their own folic acid of which para aminobenzoic acid (PABA) is a constituent – Sulfonamides, being structural analogues of PABA, inhibit bacterial folate synthase competitively.

Ans is ‘b’ i.e., Sulphadiazine

Topical Sulfonamides – Sulfacetamide sodium, Mafenide, silver sulfadiazine.

Ans. is ‘d’ i.e., Sulphonamide

o Kernicterus may be precipitated in newborn, especially premautre, by displacement of bilirubin from plasma protein binding sites.

Ans. is ‘c’ i.e., Brinzolamide

Acetazolamide, Dorzolamide and Brinzolamide are sulfonamide derivatives which act by inhibiting carbonic anhydrase (carbonic anhydrase inhibitor). Being sulphonamide derivatives they are contraindicated in patients with allergy to sulphonamides.

D. i.e. Mucous membrane is usually involved

A. i.e. Acute intermittent porphyria

Acute intermittent porphyria is a neuro visceral syndrome & should be suspected whenever a patient presents with symptoms suggesting involvement of both visceral & nervous system precipitated by drugs eg sulfonamides etcQ.

Ans. is ‘d’ i.e. Salazopyrin