From the Guidelines
Dextromethorphan is commonly found in several prescription oral combination medications, including Nuedexta (dextromethorphan/quinidine), Robitussin DM (dextromethorphan/guaifenesin), and various multi-symptom cold and flu preparations that combine dextromethorphan with antihistamines, decongestants, and sometimes acetaminophen or NSAIDs for pain relief. These combinations are prescribed based on symptom presentation, with dosing typically every 4-6 hours for cough preparations and twice daily for Nuedexta, though specific regimens should be followed according to the prescription instructions 1. The dosage of dextromethorphan can vary, but the generally recommended dosage is 10-15 mg tid or qid, with a maximum dose of 120 mg/d 1.
Some of the prescription combinations of oral preparations that include dextromethorphan are:
- Nuedexta (dextromethorphan/quinidine) for pseudobulbar affect
- Robitussin DM and similar products that combine dextromethorphan with guaifenesin for cough and congestion
- Benzonatate-DM combinations for cough suppression
- Multi-symptom cold and flu preparations that combine dextromethorphan with antihistamines (like chlorpheniramine), decongestants (like phenylephrine or pseudoephedrine), and sometimes acetaminophen or NSAIDs for pain relief
It's worth noting that the effectiveness of dextromethorphan in suppressing cough has been shown in a single meta-analysis, and the generally recommended dosage may be subtherapeutic, with maximum cough reflex suppression occurring at 60 mg 1. However, care must be taken in recommending dextromethorphan at higher doses since some combined preparations contain other ingredients such as paracetamol.
In terms of specific products, some examples include:
- Day & Night Nurse (GSK) which includes dextromethorphan and pholcodine
- Benylin Tickly Coughs
- Benylin Dry Coughs
- Actifed Multi-Action Dry Coughs
- Meltus Dry Coughs
- Robitussin for dry coughs
- Sinecod syrup which includes butamirate citrate and may be effective in managing cough in patients with lung cancer 1.
Overall, the choice of treatment will depend on the individual patient's symptoms and medical history, and the prescription combinations of oral preparations that include dextromethorphan should be used under the guidance of a healthcare professional.
From the FDA Drug Label
Active ingredient (in each 5 mL) Dextromethorphan polistirex equivalent to 30 mg dextromethorphan hydrobromide Package/Label Principal Display Panel Compare to Delsym® active ingredient Dextromethorphan Polistirex Extended-Release Oral Suspension Cough Suppressant The prescription combinations of oral preparations that include dextromethorphan are:
- Dextromethorphan polistirex equivalent to 30 mg dextromethorphan hydrobromide in a 5 mL oral suspension 2
- Dextromethorphan Polistirex Extended-Release Oral Suspension in a 3 FL OZ (89 mL) orange flavored liquid 2
From the Research
Prescription Combinations of Oral Preparations with Dextromethorphan
- The study 3 mentions a gas chromatographic method for determining combinations of active ingredients in cough and cold preparations, including dextromethorphan hydrobromide.
- The combinations of active ingredients that can be determined using this method include:
- Acetaminophen
- Phenylpropanolamine hydrochloride
- Guaifenesin
- Pseudoephedrine hydrochloride
- Caffeine
- Chlorpheniramine maleate
- Dextromethorphan hydrobromide
- These combinations are found in cough and cold tablets and syrups, indicating that dextromethorphan can be prescribed in combination with these other active ingredients in oral preparations.