1. If present, these signs include pallor, weakness,
lightheadedness, yawning, nausea, diaphoresis, hyperentilation, blurred vision, and impaired hearing immediately before the syncopal eent.
晕厥发生前，可立即出现面色苍白、虚弱无力、头晕、打哈欠、恶心、出汗、过度通气、视力模糊和听力下降。
2. In addition, the subjects who took guanfacine had significantly more somnolence,
lightheadedness, and dry mouth than those who took placebo.
另外，服用氯苯乙胍的患者比服用安慰剂的患者有更明显的嗜睡、头昏、口干等症状。
