Hey thanks for your faith in the health care magic.i have gone through your question and understood your problem. Following are side effects of Pristiq (desvenlafaxine): More common: Decreased appetite inability to have an orgasm inability to have or keep an erection loss of sexual ability, desire, drive, or performance sleepiness or unusual drowsiness sleeplessness Less common: Change in taste continuous ringing, buzzing, or other unexplained noise in the ears decreased weight difficult urination fear or nervousness hearing loss increased sensitivity of the eyes to light jitteriness lack or loss of strength loss of taste Side effects of Sandomigran include: Increased appetite, wt gain, sedation (including somnolence), fatigue, dizziness, dry mouth, nausea, constipation. Rarely, hypersensitivity reactions, face oedema, urticaria, rash, depression, CNS stimulation (eg aggression, agitation), hallucinations, insomnia, anxiety, seizures, paraesthesia, myalgia. Hope I have answered your query. If you like my answers and wish me to answer in future, bring it to my attention