Call your doctor at once if you have a serious side effect such as:
feeling short of breath, even with mild exertion;
chest pain, feeling like you might pass out;
swelling in your ankles or feet;
pounding heartbeats or fluttering in your chest;
confusion or irritability, unusual thoughts or behavior;
feelings of extreme happiness or sadness; or
dangerously
high blood pressure (
severe headache,
blurred vision, buzzing in your ears, anxiety, chest pain,
shortness of breath, uneven heartbeats, seizure).
Common phentermine side effects may include:
feeling restless or hyperactive;
headache, dizziness, tremors;
sleep problems (insomnia);
dry mouth or an unpleasant taste in your mouth;
diarrhea or
constipation, upset stomach; or
increased or decreased interest in sex, impotence.