⚠️ Warnings
The product should be administered with caution in patients with moderate to severe hepatic impairment, as the metabolism of dextromethorphan may be altered.
Dextromethorphan is metabolised via the hepatic cytochrome P450 2D6 pathway. The activity of this enzyme is genetically determined. Approximately 10% of the general population are CYP2D6 poor metabolisers. In poor metabolisers and in patients receiving concomitant CYP2D6 inhibitors, more pronounced and/or prolonged effects of dextromethorphan may occur. Caution is therefore required in CYP2D6 poor metabolisers and in patients taking CYP2D6 inhibitors (see also section 4.5).
If cough persists for more than one week, or is accompanied by high fever, rash, or persistent headache, the patient should seek medical attention.
Dextromethorphan has a mild potential for dependence. With prolonged use, patients may develop tolerance and psychological and physical dependence. Patients with a tendency towards substance misuse or development of dependence should use this product only for short periods and under close medical supervision.
Cases of dextromethorphan misuse and dependence have been reported. Particular caution is advised in adolescents and young adults, as well as in patients with a history of substance or psychoactive drug use.
Given the potential for dextromethorphan misuse, prescribers should assess whether patients have a history of drug abuse and should closely monitor such patients for signs of misuse or abuse (e.g. development of tolerance, dose escalation, drug-seeking behaviour).
The potential for misuse of dextromethorphan should be taken into account, as it may produce serious adverse reactions (see also sections 4.8 Undesirable effects and 4.9 Overdose).
Risk arising from concomitant use of sedatives such as benzodiazepines or related drugs
Concomitant use of Dextromethorphan Nutra Essential with sedatives such as benzodiazepines or related drugs may result in sedation, respiratory depression, coma, and death. Because of these risks, concomitant prescribing of such sedatives should be reserved for patients in whom alternative treatment options are not feasible. Where the decision is made to prescribe Dextromethorphan Nutra Essential concomitantly with sedatives, the lowest effective dose should be prescribed for the shortest possible duration of treatment.
Patients should be closely monitored for signs and symptoms of respiratory depression and sedation. In this regard, it is strongly recommended that patients and their caregivers be informed so that they are aware of these symptoms (see section 4.5).
Serotonin syndrome
Serotonergic effects, including the development of potentially life-threatening serotonin syndrome, have been reported with dextromethorphan when administered concomitantly with serotonergic agents such as selective serotonin reuptake inhibitors (SSRIs), drugs that impair the metabolism of serotonin (including monoamine oxidase inhibitors [MAOIs]), and CYP2D6 inhibitors.
Serotonin syndrome may include changes in mental status, autonomic instability, neuromuscular abnormalities, and/or gastrointestinal symptoms.
If serotonin syndrome is suspected, treatment with Dextromethorphan Nutra Essential should be discontinued.
Warnings regarding excipients
This medicinal product contains maltitol solution, which may have a mild laxative effect. Patients with rare hereditary problems of fructose intolerance should not take this product. This medicinal product contains less than 1 mmol (23 mg) sodium per ml, that is to say essentially "sodium-free". This medicinal product contains 1 mg of sodium benzoate per ml.