At a dosage of 30mg of phenelzine, what adverse effect must be monitored?

At a dosage of 30mg of phenelzine, monitoring for dizziness is crucial due to its potential to cause hypotension, particularly postural hypotension. Phenelzine is a monoamine oxidase inhibitor (MAOI) commonly used in the treatment of depression, and it can lead to changes in blood pressure regulation. This effect arises because MAOIs can increase norepinephrine levels, which may alter vascular tone and lead to symptoms like dizziness when standing up or changing positions swiftly. Thus, patients taking phenelzine should be closely observed for any signs of dizziness to help manage and mitigate this adverse effect effectively.

Monitoring for other side effects such as facial flushing, increased secretions, or diarrhea is also important, but dizziness stands out as a significant concern due to its implications for patient safety and comfort, particularly as they might experience falls or injury due to lightheadedness.