Which food item should be avoided by a client on phenelzine sulfate (Nardil)?

For a client taking phenelzine sulfate, it's important to recognize that this medication is a monoamine oxidase inhibitor (MAOI), which can interact negatively with certain foods, particularly those containing tyramine. Tyramine is an amino acid that can cause dangerous hypertensive crises when ingested in large amounts while on MAOIs.

Avocado is a significant food item to avoid because it contains high levels of tyramine, particularly in its overripe state. Consuming tyramine-rich foods while on an MAOI like phenelzine can lead to severe increases in blood pressure and could result in serious health complications. Therefore, avoiding avocados is crucial for maintaining safety and health for someone on this medication.

In contrast, pasta, chocolate, and yogurt have either negligible or safe levels of tyramine when consumed in typical dietary amounts. This is why those options would not typically pose the same risk for someone taking phenelzine sulfate, making avocado the correct choice to avoid in this context.