Can cause withdrawal symptoms
nausea
vomiting
constipation
drowsiness
confusion
difficulty in micturition
ureteric or biliary spasms
urinary retention
dry mouth
dizziness
sweating
facial flushing
headache
vertigo
bradycardia
tachycardia
palpitations
orthostatic hypotension
hypothermia
restlessness
mood changes
decreased libido or potency
hallucination
miosis; raised intracranial pressure
muscle rigidity.