The most commonly reported undesirable effects during the clinical trials performed with the paracetamol/tramadol combination were nausea, dizziness and somnolence, observed in more than 10% of the patients.
Within each frequency grouping, undesirable effects are presented in order of decreasing seriousness.
Cardiovascular system disorders:
• Uncommon (≥1/1000 to < 1/100): palpitations, tachycardia, arrhythmia.
Central and peripheral nervous system disorders:
• Very common ((≥1/10): dizziness, somnolence
• Common ((≥1/100 to < 1/10): headache trembling
• Uncommon ((≥1/1000 to < 1/100): involuntary muscular contractions, paraesthesia, tinnitus
• Rare (≥1/10000 to < 1/1000): ataxia, convulsions, syncope, speech disorder.
Psychiatric disorders:
• Common (≥1/100 to < 1/10): confusion state, mood changes (anxiety, nervousness, euphoria), sleep disorders
• Uncommon (≥1/1000 to < 1/100): depression, hallucinations, nightmares, amnesia
• Rare (≥1/10000 to < 1/1000): delirium, drug dependence
Post marketing surveillance
• Very rare (< 1/10000): abuse.
Vision disorders:
• Rare (≥ 1/10000 to < 1/1000): blurred vision, miosis, mydriasis
Ear and labyrinth disorders:
• Uncommon: tinnitus
Respiratory, thoracic and mediastinal disorders:
• Uncommon ((≥1/1000 to < 1/100): dyspnoea
• Frequency unknown (cannot be estimated from the available data): hiccups
Gastro-intestinal disorders:
• Very common (≥1/10) : nausea
• Common (≥1/100 to < 1/10): vomiting, constipation, dry mouth, diarrhoea abdominal pain, dyspepsia, flatulence
• Uncommon (≥ 1/1000 to < 1/100): dysphagia, melaena
General disorders and administration site conditions:
• Uncommon: chills, chest pain
Liver and biliary system disorders:
• Uncommon (≥ 1/1000 to < 1/100): hepatic transaminases increase
Skin and appendages disorders:
• Common (≥ 1/100 to < 1/10) : sweating, pruritus
• Uncommon (≥ 1/1000 to < 1/100): dermal reactions (e.g.rash, urticaria)
Renal and Urinary system disorders:
• Uncommon (≥ 1/1000 to < 1/100): albuminuria, micturition disorders (dysuria and urinary retention)
Body as a whole:
• Uncommon ((≥1/1000 to < 1/100): shivers, hot flushes, thoracic pain
Metabolism and nutrition disorders:
• Unknown: hypoglycaemia
Although not observed during clinical trials, the occurrence of the following undesirable effects known to be related to the administration of tramadol or paracetamol cannot be excluded:
Tramadol
• Postural hypotension, bradycardia, collapse (tramadol).
• Post-marketing surveillance of tramadol has revealed rare alterations of warfarin effect, including elevation of prothrombin times.
• Rare cases (≥1/10000 to <1/1000): allergic reactions with respiratory symptoms (e.g. dyspnoea, bronchospasm, wheezing, angioneurotic oedema) and anaphylaxis.
• Rare cases (≥1/10000 to <1/1000): changes in appetite, motor weakness and respiratory depression.
• Psychic side effects may occur following administration of tramadol which vary individually in intensity and nature (depending on personality and duration of medication). These include changes in mood, (usually elation occasionally dysphoria), changes in activity (usually suppression, occasionally increase), and changes in cognitive and sensorial capacity (e.g. decision behaviour, perception disorders).
• Worsening of asthma has been reported though a causal relationship has not been established.
• Symptoms of withdrawal reactions, similar to those
occurring during opiate withdrawal may occur as follows: agitation, anxiety, nervousness, insomnia, hyperkinesia, tremor and gastrointestinal symptoms. Other symptoms that have very rarely been seen if tramadol hydrochloride is discontinued abruptly include: panic attacks, severe anxiety, hallucinations, paraesthesia, tinnitus and unusual CNS symptoms.
• Not known (cannot be estimated from the available data): serotonin syndrome
Paracetamol
• Adverse effects of paracetamol are rare, but hypersensitivity including skin rash may occur. There have been reports of blood dyscrasias, including thrombocytopenia and agranulocytosis, but these were not necessarily causally related to paracetamol.
• There have been several reports that suggest that paracetamol may produce hypoprothrombinaemia when administered with warfarin-like compounds. In other studies, prothrombin time did not change.
• Very rare cases of serious skin reactions have been reported.
• Not known (cannot be estimated from the available data): High anion gap metabolic acidosis
Description of selected adverse reactions
High anion gap metabolic acidosis
Cases of high anion gap metabolic acidosis due to pyroglutamic acidosis have been observed in patients with risk factors using paracetamol (see section 4.4). Pyroglutamic acidosis may occur as a consequence of low glutathione levels in these patients.
Drug dependence
Repeated use of Tramadol and Paracetamol can lead to drug dependence, even at therapeutic doses. The risk of drug dependence may vary depending on a patient's individual risk factors, dosage, and duration of opioid treatment (see section 4.4).
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme; website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.