Dextromethorphan Hydrobromide: Antitussive Salt Form
Dextromethorphan hydrobromide is the salt form of the active ingredient dextromethorphan, which is used in most cough suppressants (antitussives). Patients frequently encounter this longer designation on package inserts and in pharmaceutical reference lists when examining their cough medicine more closely. Pharmacologically, it works the same as dextromethorphan, with the hydrobromide being the salt-forming component that improves the water solubility and stability of the active ingredient. In Germany, dextromethorphan hydrobromide is found in many over-the-counter cough syrups and cough suppressant tablets and is used to treat dry irritating cough.
Well-known brand names containing dextromethorphan hydrobromide include Wick MediNait, Sedotussin Hustenstiller, NeoTussan, Hustenstiller ratiopharm, and several others. Detailed information about the active ingredient dextromethorphan can be found on our dextromethorphan main page. This page focuses on the salt form and practical guidance on using cough suppressants containing dextromethorphan hydrobromide.
Definition
Pharmacologically, dextromethorphan is the effective substance. In purely chemical terms, it is combined with hydrobromic acid (HBr) as a salt for improved stability and water solubility, resulting in dextromethorphan hydrobromide. In the body, the salt dissociates and releases active dextromethorphan, which then exerts its effect on the cough center. An alternative salt form is dextromethorphan polistirex, which is found in some sustained-release formulations.
The difference between dextromethorphan and dextromethorphan hydrobromide is purely formulation-related and does not affect the active ingredient itself. In pharmacy counseling or medical prescriptions, the designations are often used interchangeably. Dosing is always based on the salt dextromethorphan hydrobromide because this is the form contained in the product.
Mechanism of Action
Dextromethorphan acts on the cough center in the medulla oblongata and centrally suppresses the cough reflex. Unlike codeine, dextromethorphan has minimal analgesic and minimal addictive potential at therapeutic doses. The antitussive effect is mediated by binding to sigma 1 receptors and through NMDA antagonism. Detailed pharmacological information can be found on the dextromethorphan main page.
Indications
- Dry irritating cough associated with colds, acute bronchitis, or other viral respiratory tract infections
- Coughing episodes at night that interfere with sleep
- Irritating cough following airway irritation, including after inhalation of irritant gases or dust
- Adjuvant in symptomatic cold therapy in combination products with decongestants and analgesics
Dextromethorphan hydrobromide is not suitable for productive cough with mucus formation, as cough suppression can hinder secretion clearance and promote mucus accumulation.
Dosage and Administration
Adults and adolescents aged 12 years and over: 10 to 30 mg every 4 to 6 hours, maximum 120 mg per day. For sustained-release formulations, 60 mg twice daily.
Children 6 to 11 years: 5 to 15 mg every 4 to 6 hours, maximum 60 mg per day. For younger children, only after medical consultation.
Duration of use: typically 3 to 5 days, medical evaluation is required for prolonged symptoms.
Administration: Take tablets, drops, or syrup with water, regardless of meals. Shake syrup well before use.
Renal impairment: generally no dose adjustment required. Hepatic impairment: use caution with severe impairment due to accumulation, consider dose reduction.
Important: not to be combined with MAO inhibitors, risk of serotonin syndrome. Minimum interval of 14 days after discontinuation of an MAO inhibitor.
Side Effects
Common: drowsiness, dizziness, nausea, vomiting, gastrointestinal disturbances, dry mouth.
Occasional: constipation, confusion, sleep disturbances, tachycardia, allergic skin reactions.
Rare to very rare: hallucinations, dissociative effects (especially with overdose), respiratory depression at very high doses, anaphylactic reactions, serotonin syndrome when combined with serotonergic agents.
In case of overdose: agitation, coordination disorders, hallucinations, tachycardia, tachypnea, hyperreflexia, seizures, respiratory depression, coma. Emergency requiring symptomatic treatment and possibly naloxone.
Note: Dextromethorphan has dissociative abuse potential at high doses, which is why pharmacy dispensing is limited.
Drug Interactions
- MAO inhibitors (tranylcypromine, linezolid, selegiline): contraindication, risk of serotonin syndrome with hyperthermia and cardiovascular shock.
- SSRIs, SNRIs, other serotonergic agents (fluoxetine, citalopram, tramadol, triptans): risk of serotonin syndrome, caution and combination only under medical supervision.
- CYP2D6 inhibitors (paroxetine, fluoxetine, bupropion, quinidine, terbinafine): elevated dextromethorphan levels, caution.
- Other centrally depressant substances (alcohol, benzodiazepines, antihistamines): additive sedation.
- Antitussives and mucolytics (acetylcysteine, ambroxol): combination may promote mucus accumulation, avoid concurrent use.
- Bromide ions from the salt: with chronic high-dose use, bromism theoretically possible, clinically practically irrelevant.
Special Precautions
Pregnancy: not in the first 3 months, thereafter only with strict indication in the lowest effective dose. Breast-feeding: transfer into breast milk, caution and possibly discontinue breast-feeding.
Children: available over-the-counter from 6 years of age, in younger children only after medical consultation.
Contraindications: known hypersensitivity, concurrent or recently discontinued MAO inhibitor therapy, severe respiratory disease with insufficiency, productive cough, infants under 2 years, asthma in acute phase.
Before use: medical evaluation is mandatory for cough lasting longer than 3 weeks, hemoptysis, dyspnea, fever, or unusual accompanying symptoms.
During therapy: if symptoms do not improve or worsen, medical consultation is necessary.
Lifestyle: no alcohol during therapy due to additive central depression. In smokers, additional risk for persistent cough symptoms.
Driving ability: dextromethorphan can cause drowsiness and dizziness, therefore use caution when driving or operating heavy machinery, especially when first starting treatment.
You might also be interested in
- Dextromethorphan, main page for this active ingredient
- Codeine, opioid antitussive for irritating cough
- Pentoxyverin, another centrally acting antitussive
- Acetylcysteine, secretolytic for productive cough
- Ambroxol, mucolytic for thick mucus
Frequently Asked Questions
Is dextromethorphan hydrobromide the same as dextromethorphan?
Pharmacologically yes. Dextromethorphan hydrobromide is only the salt form with hydrobromic acid, which is used in most cough medicines. In the body, the active ingredient dextromethorphan is released and exerts its antitussive effect. The dosage is based on the salt form because it corresponds to the form contained in the product.
When should I not take dextromethorphan?
Not with productive cough with mucus, because the cough is suppressed. Also not with concurrent or recently discontinued MAO inhibitor therapy due to risk of serotonin syndrome. Use caution with asthma in acute phase, severe lung disease with insufficiency, and in the first 3 months of pregnancy. For cough lasting longer than 3 weeks, hemoptysis, or dyspnea, medical evaluation is necessary.
Is dextromethorphan hydrobromide addictive?
Dextromethorphan is not a controlled substance at therapeutic doses. At very high doses, dissociative effects with hallucinations can occur, which is why dextromethorphan is monitored for abuse potential in some countries. In Germany, pharmacy dispensing of larger quantities is limited to prevent abuse. With proper use, the risk is low.
What does the term hydrobromide at the end of the name mean?
Hydrobromide designates the salt form of the active ingredient with hydrobromic acid. This salt formation improves the water solubility and stability of the active ingredient in the tablet or syrup. The bromide ions contained are not pharmacologically relevant at the usual dosage. The active ingredient is released in the body after ingestion and exerts its antitussive effect.
Sources
- Gelbe Liste, Dextromethorphan active ingredient profile
- BfArM, Federal Institute for Drugs and Medical Devices
- AWMF Guidelines on acute and chronic cough
Legal Notices and Disclaimer
The information provided on this page is for general informational purposes only and does not constitute medical advice, diagnosis, or treatment recommendation. It does not replace the advice of a licensed physician or pharmacist. All information is based on expert information published at the time of creation and recognized scientific sources, with the manufacturer's current technical information always being authoritative. Sanoliste assumes no liability for completeness, currency, or accuracy of the information presented. In case of a medical emergency, call emergency number 112.