Dapaxetine and sildenafil belong to different pharmacological mechanisms of drugs, can not compare the differences in side effects of different individuals, it is recommended to use under the guidance of a professional male physician, can minimize the possibility of side effects. 1. Dapaxetine is a potent selective 5-hydroxytryptamine reuptake inhibitor, playing a therapeutic role in the treatment of premature ejaculation may be related to the inhibition of neuronal reuptake of 5-hydroxytryptamine to enhance the role of neurotransmitters in the pre and post-synaptic receptors. Adverse effects include headache, dizziness, nausea, diarrhea, insomnia, and fatigue. 2. Sildenafil is a selective inhibitor of cyclic guanosine monophosphate-specific phosphodiesterase type 5, which can help erectile function by inhibiting phosphodiesterase type 5 in the corpus cavernosum. Adverse effects include headache, flushing, dyspepsia, abnormal vision, nasal congestion, back pain, and myalgia. The two drugs work differently, individuals have different sensitivity and tolerance to drugs, and it is not possible to compare the differences in side effects. It is recommended that the medication be evaluated under the guidance of a physician for safe use, to avoid harm caused by self-medication.