Question 1

A premixed combination of trimethoprim and sulfamethoxazole is called:&#10;A) trimethoxazole.&#10;B) co-trimoxazole.&#10;C) sulphaprim.&#10;D) blephamide.

Accepted Answer

The premixed combination of trimethoprim and sulfamethoxazole is called co-trimoxazole. A is incorrect because trimethoxazole is not the correct nomenclature for this combination. C is incorrect because sulphaprim is not the correct nomenclature for this combination. D is incorrect because Blephamide is an ophthalmic medication used to treat eye infections and contains sulfacetamide sodium and prednisolone acetate, not trimethoprim and sulfamethoxazole.

Question 2

During treatment with selected sulfonamides,a client may experience diarrhoea.This usually indicates:&#10;A) a change in the balance of gut flora.&#10;B) gastrointestinal tract bleeding.&#10;C) drug crystallisation.&#10;D) an allergic reaction.

Accepted Answer

Diarrhoea during treatment with sulfonamides usually indicates a change in the balance of gut flora, which can result from the suppression of normal gut bacteria by the medication. This can lead to overgrowth of harmful bacteria, causing diarrhoea. Gastrointestinal tract bleeding, drug crystallisation, or an allergic reaction are less likely causes of this symptom.

Question 3

Trimethoprim is best taken as a single daily dose:&#10;A) in the morning.&#10;B) at midday.&#10;C) in the mid-afternoon.&#10;D) at bedtime.

Accepted Answer

Trimethoprim is usually taken once a day, at bedtime or with the evening meal, to prevent stomach upset. This ensures that the drug is absorbed thoroughly and that it remains in the body for an extended period, allowing it to combat the infection effectively. Taking it earlier in the day may lead to higher rates of side effects such as nausea and dizziness. Therefore, the best choice is at bedtime.

Question 4

What should a person be advised to do when taking sulfonamide therapy?&#10;A) Ensure an adequate fluid intake.&#10;B) Monitor folate status during high-dose or prolonged therapy.&#10;C) Have a full blood examination during high-dose or prolonged therapy.&#10;D) All of the above.

Accepted Answer

Sulfonamide therapy can cause various adverse effects such as kidney damage, blood disorders, and lowered folate levels. Therefore, it is important for the person taking the medication to ensure an adequate fluid intake, monitor their folate status, and have a full blood examination during high-dose or prolonged therapy. Therefore, all of the above options should be advised.

Question 5

The actions of the sulfonamides and trimethoprim:&#10;A) are considered bactericidal.&#10;B) are identical, as they interrupt the process at the same point.&#10;C) interfere with nucleic acid synthesis.&#10;D) are not influenced by folic acid stores.

Accepted Answer

Sulfonamides and trimethoprim interfere with the bacterial synthesis of folic acid, which is necessary for nucleic acid synthesis. Sulfonamides inhibit the enzyme dihydropteroate synthase, while trimethoprim inhibits dihydrofolate reductase, both steps in the folic acid pathway.

Deck 68: Sulfonamides and Trimethoprim