An elderly male presents with a sore throat; which drug is most likely to be the cause of the adverse reaction?

An elderly male presents with a sore throat; which drug is most likely to be the cause of the adverse reaction?

• A. Finasteride
• B. Fluoxetine
• C. Clarithromycin
• D. Methotrexate

Answer: (D)

Mucositis from methotrexate is a classic adverse effect that can present as a sore throat. Methotrexate disrupts DNA synthesis in rapidly dividing cells, including the lining of the mouth and throat. This leads to inflammation and ulceration of mucosal surfaces, known as mucositis, which often manifests as a painful or sore throat in patients, especially the elderly who are more susceptible due to reduced mucosal resilience and possible concurrent therapies. The other drugs don’t typically produce mucosal throat toxicity. Finasteride is a 5-alpha-reductase inhibitor used for BPH and hair loss, with effects mainly on sexual function rather than mucosal irritation. Fluoxetine, an SSRI, can cause nausea, sleep changes, or sexual side effects, but sore throat from mucositis isn’t characteristic. Clarithromycin is a macrolide antibiotic with adverse effects like GI upset or QT prolongation; sore throat is not a typical or direct adverse reaction. So the sore throat is most plausibly linked to methotrexate’s mucositis.

Mucositis from methotrexate is a classic adverse effect that can present as a sore throat. Methotrexate disrupts DNA synthesis in rapidly dividing cells, including the lining of the mouth and throat. This leads to inflammation and ulceration of mucosal surfaces, known as mucositis, which often manifests as a painful or sore throat in patients, especially the elderly who are more susceptible due to reduced mucosal resilience and possible concurrent therapies.

The other drugs don’t typically produce mucosal throat toxicity. Finasteride is a 5-alpha-reductase inhibitor used for BPH and hair loss, with effects mainly on sexual function rather than mucosal irritation. Fluoxetine, an SSRI, can cause nausea, sleep changes, or sexual side effects, but sore throat from mucositis isn’t characteristic. Clarithromycin is a macrolide antibiotic with adverse effects like GI upset or QT prolongation; sore throat is not a typical or direct adverse reaction.

So the sore throat is most plausibly linked to methotrexate’s mucositis.