The common side effects reported with Paroxetine are nausea, somnolence, insomnia, agitation, nervousness, tremor, dry mouth, constipation, flatulence, asthenia, abnormal ejaculation, sweating, libido decreased, dizziness and impotence. Some of the rarer side effects reported during clinical trials are irregular heartbeats, chest pain, changes in the mood and buzzing or ringing in the ears.