Side Effect :

Sibutramine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

headache
change in appetite
constipation
heartburn
dry mouth
weakness
back pain
nervousness
difficulty falling asleep or staying asleep
runny nose
flu-like symptoms
flushing
painful menstrual periods

Some side effects can be serious. The following symptoms are uncommon, but if you experience any of them, call your doctor immediately:

fast or pounding heart beat
chest pain
shortness of breath
upset stomach
stomach pain
vomiting
extreme excitement
restlessness
anxiety
depression
dizziness
lightheadedness
fainting
confusion
uncoordinated or abnormal movement
muscle stiffness
shaking hands that you cannot control
seizures
shivering
excessive sweating
fever
sore throat
large pupils (black area in center of eyes)
change in vision
eye pain
hives
skin rash
itching
difficulty speaking, breathing, or swallowing
hoarseness
swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
unusual bleeding or bruising

Sibutramine may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.