INDICATION AND DOSAGE OF DEXTROMETHORPHAN

What It Is

Dextromethorphan (DXM) is a cough suppressant commonly found in over-the-counter (OTC) medications. It is used to alleviate cough symptoms associated with colds and other respiratory conditions. Unlike some other cough medications, dextromethorphan does not directly treat the underlying cause of the cough but rather works to reduce the frequency and intensity of the cough reflex.

Dosage Forms and Strengths

Dextromethorphan is available in various dosage forms, including:

• Oral Tablets: Typically available in strengths of 10 mg, 20 mg, and 30 mg.
• Oral Syrups: Usually available in concentrations of 10 mg/5 mL or 15 mg/5 mL.
• Extended-Release Capsules: Often found in strengths of 60 mg.
• Lozenges: Generally available in 5 mg and 10 mg doses.

These forms allow for flexible administration depending on the specific needs of the patient.

Brand and Generic Names

Dextromethorphan is marketed under numerous brand names, including:

• Robitussin DM
• Delsym
• NyQuil Cough
• Mucinex DM

The generic name for this compound is simply "Dextromethorphan."

Indications for Use

Dextromethorphan is indicated for the relief of cough caused by the common cold or other respiratory conditions. It is typically recommended for use when a dry, non-productive cough interferes with daily activities or sleep. It is not intended for use in treating coughs related to smoking, chronic bronchitis, or emphysema.

Mechanism of Action

Dextromethorphan acts centrally in the brain to suppress the cough reflex. It is a non-opioid cough suppressant that works primarily on the cough center in the medulla oblongata of the brain. By inhibiting the neural signals that trigger coughing, dextromethorphan helps reduce the frequency and intensity of cough episodes.

Administration and Dosage

The dosage of dextromethorphan depends on the specific product and patient age. General dosing guidelines include:

• For adults and children over 12 years: 10 mg to 20 mg every 4 to 6 hours as needed, not exceeding 120 mg per day.
• For children aged 6 to 12 years: 5 mg to 10 mg every 4 to 6 hours as needed, not exceeding 60 mg per day.
• For children aged 2 to 6 years: 2.5 mg to 5 mg every 4 to 6 hours as needed, not exceeding 30 mg per day.

Extended-release formulations are usually dosed less frequently, typically every 12 hours.

Side Effects and Precautions

Common side effects of dextromethorphan include:

• Drowsiness
• Dizziness
• Nausea
• Vomiting
• Stomach upset

Less common but more severe side effects may include:

• Allergic reactions (rash, itching, swelling)
• Confusion or hallucinations (particularly at high doses)
• Serotonin syndrome (if taken in conjunction with other serotonergic medications)

Precautions include:

• Avoiding use in patients with a history of hypersensitivity to dextromethorphan or any other components of the formulation.
• Caution is advised when administering to patients with a history of substance abuse, as high doses can lead to abuse or dependency.
• Avoiding concurrent use with other cough and cold medications or alcohol to prevent potential interactions and compounded side effects.

Conclusion

Dextromethorphan is an effective and widely used cough suppressant that provides symptomatic relief from coughs associated with colds and respiratory conditions. Available in various dosage forms and strengths, it is suitable for use in both adults and children, with specific dosing guidelines based on age. While generally well-tolerated, it is important to use dextromethorphan responsibly and be aware of potential side effects and interactions. As with any medication, it is essential to follow the dosing instructions and consult a healthcare provider if there are any concerns or questions regarding its use.