NursingSprint

✔️ A drug interaction occurs when the effect of one drug is altered by the presence of another drug, food, or substance — in this case, antacid affecting ketoconazole’s absorption.

✔️ Antacids raise gastric pH, which can impair the dissolution and absorption of ketoconazole, an antifungal that requires an acidic environment for proper bioavailability.

✔️ This is a pharmacokinetic interaction affecting the absorption phase, leading to a reduced therapeutic effect of ketoconazole.

✔️ Nurses must assess for potential administration timing conflicts between medications and educate clients to space the administration (e.g., giving ketoconazole 2 hours before or after the antacid).

✔️ Recognizing drug interactions is essential to prevent treatment failure and ensure the intended clinical response is achieved.

Educational Insight:

Many medications interact based on gastric pH, enzyme systems (like CYP450), or protein binding. The nurse plays a key role in reviewing all concurrent medications and educating patients on appropriate timing and compatibility to prevent adverse interactions and ensure therapeutic effectiveness.

Incorrect Options:

“A. Allergic reaction”

⯈ An allergic reaction involves an immune-mediated response (e.g., rash, anaphylaxis) to a drug and is not related to absorption or bioavailability changes caused by another substance.

“B. Displacement”

⯈ Displacement refers to one drug dislodging another from protein-binding sites, increasing free drug levels — this does not apply to absorption changes in the stomach.

“C. Accumulation”

⯈ Accumulation describes drug build-up due to impaired metabolism or excretion, not impaired dissolution or absorption due to pH changes from antacids.