What adverse effect should a client prescribed Phenelzine sulfate (Nardil) report immediately?

Neck stiffness or soreness is a concerning symptom for a client taking Phenelzine sulfate, which is a monoamine oxidase inhibitor (MAOI) used primarily for treating depression. This medication can cause hypertensive crises, particularly when certain dietary restrictions are not adhered to, such as avoiding tyramine-rich foods. One of the signs of such a crisis can be rigidity or stiffness in the neck, which may accompany symptoms like severe headache, increased blood pressure, and potential agitation.

Prompt reporting of neck stiffness or soreness is critical as it may indicate a serious reaction that requires immediate medical intervention to prevent further complications. This awareness helps ensure that any adverse responses to the medication can be managed effectively and that the client's safety is prioritized.