Final answer:
The patient is likely experiencing benzodiazepine withdrawal from discontinuing lorazepam, given the match between her symptoms and the expected withdrawal effects of this medication.
Step-by-step explanation:
The patient in the scenario is experiencing symptoms such as insomnia, restlessness, headache, and nausea after having stopped taking lorazepam, which is a benzodiazepine, that was used on an as-needed basis for the past five years. The last dose was taken 3 days ago, and the patient is likely experiencing benzodiazepine withdrawal. Lorazepam is known to be used to relieve anxiety, induce sleep, prevent seizures, and sedate, which suggests that the patient's symptoms are consistent with withdrawal from this type of medication.
Benzodiazepines carry a risk of dependence and withdrawal, especially with prolonged use such as in this patient's case. Patients need to discontinue such medications under medical supervision to avoid adverse side effects and potentially dangerous withdrawal symptoms. Hence, the nurse should suspect that the patient is experiencing d. benzodiazepine withdrawal.