Less serious side effects may include: 1  cough; 2  loss of taste sensation, loss of appetite; 3  dizziness, drowsiness, headache; 4  sleep problems (insomnia);5  dry mouth; 6  nausea, vomiting, diarrhea; or. 7  mild skin itching or rash. loss of taste sensation, loss of appetite; 2  dizziness, drowsiness, headache; 3  sleep problems (insomnia); 4  dry mouth; 5  nausea, vomiting, diarrhea; or. 6  mild skin itching or rash.