Generic rivastigmine side effects are the following: nausea, vomiting, loss of appetite, heartburn or indigestion, stomach pain, weight loss, diarrhea, constipation, gas, weakness, dizziness, headache, extreme tiredness, lack of energy, tremor or worsening of tremor, increased sweating, difficulty falling asleep or staying asleep, and confusion. The following side effects are not common and may be serious, call your doctor immediately if you experience fainting, black and tarry stools, red blood in stools, bloody vomit, vomiting material that looks like coffee grounds, difficulty urinating, painful urination, seizures, depression, anxiety, aggressive behavior, hearing voices or seeing things that do not exist, uncontrollable movements, and muscle contractions.