What is the effective prescription of antitussive (cough suppressant) medications, such as cough syrups, for patients with cough?

From the Guidelines

For effective prescription of antitussive medications, such as cough syrups, in patients with cough, it is crucial to first determine the type of cough and its underlying cause, and then consider the use of opioids like hydrocodone or dihydrocodeine for severe cases, as they have been shown to be effective in suppressing cough in patients with lung cancer 1. When managing cough, it's essential to consider the patient's overall condition, including any underlying diseases or symptoms that may be contributing to the cough.

• For productive coughs with phlegm, guaifenesin (Mucinex) at 200-400mg every 4 hours can help thin secretions.
• For dry, non-productive coughs, dextromethorphan (DM) at 10-30mg every 4-8 hours suppresses the cough reflex.
• In cases with significant nighttime symptoms, diphenhydramine-containing formulations like Benadryl (25mg) can be added at bedtime.
• Codeine-containing syrups (10-20mg codeine per dose) should be reserved for severe cases due to addiction potential and are often restricted.
• Limit prescription duration to 7-10 days for most acute coughs.
• Dosing should be adjusted for children based on weight or age using pediatric formulations.
• Patients should be advised to maintain hydration, use humidifiers, and avoid irritants. According to the most recent and highest quality study available, opioids such as hydrocodone or dihydrocodeine are recommended for the management of cough in patients with lung cancer, due to their effectiveness in suppressing cough 1. It's also important to note that cough syrups work through different mechanisms: expectorants loosen mucus, antitussives suppress the cough center in the brain, antihistamines reduce postnasal drip, and opioids directly suppress the cough center but carry dependency risks. If a cough persists beyond two weeks or is accompanied by concerning symptoms like fever, shortness of breath, or blood, further evaluation is necessary to determine the underlying cause and develop an appropriate treatment plan 1.

From the FDA Drug Label

Helps loosen phlegm (mucus) and thin bronchial secretions to make coughs more productive. WARNINGS Ask a doctor before use if you have cough that occurs with too much phlegm (mucus) cough that lasts or is chronic such as occurs with smoking, asthma, chronic bronchitis, or emphysema Package/Label Principal Display Panel Compare to Delsym® active ingredient Dextromethorphan Polistirex Extended-Release Oral Suspension Cough Suppressant

The effective prescription of antitussive (cough suppressant) medications, such as cough syrups, for patients with cough is not explicitly stated in the provided drug labels.

• The labels provide information on the uses of guaifenesin, which is to loosen phlegm and thin bronchial secretions to make coughs more productive 2.
• The labels also provide warnings for the use of guaifenesin and dextromethorphan, including asking a doctor before use if the patient has a chronic cough or is hypersensitive to any of the ingredients 2.
• Dextromethorphan is listed as a cough suppressant 3. However, the labels do not provide a clear prescription or dosage instruction for the use of these medications as antitussives.

From the Research

Effective Prescription of Antitussive Medications

The effective prescription of antitussive (cough suppressant) medications, such as cough syrups, for patients with cough involves considering the underlying cause of the cough and the patient's overall health status.

• Treatment of the underlying cause(s) of cough with specific treatments should be the first approach, but suppression of cough may be necessary if this approach is not successful 4.
• Centrally acting opioids, such as morphine, codeine, and dextromethorphan, are commonly used cough suppressants, but their efficacy may vary and they can have side effects 4, 5, 6, 7.
• Peripherally acting antitussives, such as moguisteine and levodropropizine, are also available, but their effectiveness may be limited 7.

Selection of Antitussives

The selection of antitussives for prescription depends on various factors, including:

• The patient's current medications and medical history 5
• The availability of routes of administration 5
• The presence of other symptoms and potential side effects 5
• The patient's history of drug abuse 5

Efficacy of Antitussives

Studies have shown that:

• Codeine, dextromethorphan, and guaifenesin are equally effective in relieving cough symptoms in patients with uncomplicated respiratory tract infections 8
• Dextromethorphan may be more effective than codeine in reducing cough intensity in patients with chronic cough 6
• Slow-release morphine can be useful in controlling intractable cough with good tolerance to constipation and drowsiness 7

Future Directions

New agents, such as nociceptin or antagonists of TRPV1, may turn out to have antitussive effects and provide more effective treatment options for patients with chronic cough 4, 7.