In normal doses, the most common side-effects of opioid analgesics are nausea, vomiting, constipation, drowsiness, and confusion; tolerance generally develops with long-term use, but not to constipation. Micturition may be difficult and there may be ureteric or biliary spasm; there is also an anti diuretic effect. Dry mouth, sweating, facial flushing, vertigo, bradycardia, palpitations, orthostatic hypotension, hypothermia, restlessness, changes of mood, hallucinations, and miosis may also occur. These effects tend to occur more commonly in ambulant patients than n those at rest in bed and in those without severe pain. Raised intracranial pressure occurs in some patients.
Muscle rigidity has been reported following high doses.
Tramadol Hydrochloride was administrated to 550 patients during the double-blind or open-label extension periods in US studies of
chronic non malignous pain. The most frequently reported events were in the central nervous system and gastrointestinal system.
Body as a whole:
Malaise, Allergic reaction, Accidental injury, weight loss, anaphylaxis, Suicide tendency.
Vasodilation, Syncope, Orthostatic Hypotension, Tachycardia, Abnormal ECG, Hypertension, Hypotension, Myocardial
Central nervous system:
Anxiety, confusion, coordination disturbance, Euphoria, Nervousness, Sleep Disorder, Seizure, Migraine,
Abdominal pain, Anorexia, Flatulence, Gastrointestinal bleeding, Hepatitis, Stomatitis.
Rash, Urticaria, Vesicles, Steven-Johnson Syndrome/Toxic epidermal necrolysis.
Visual Disturbances, Dysgeusia.
Urinary retention, Urinary frequency, Menopausal symptoms, Dysuria, Menstrual disorder.