What is the fine-grained topic of the following text: In sensitive patients, concurrent use with alcohol or other CNS depressants may cause additional reductions in alertness and impairment of performance.Clinical studies have shown that cetirizine at the recommended dosage has minor undesirable effects on the CNS, including somnolence, fatigue, dizziness and headache. Only return the topic.
Side effects of cetirizine and interactions with other CNS depressants