What are the recommended treatments for dry coughs, specifically over-the-counter (OTC) cough syrups?

Recommended Treatments for Dry Coughs: OTC Cough Syrups

For adults with dry cough, dextromethorphan-containing cough syrups are the most effective OTC treatment option, while honey is recommended for children rather than OTC medications which show limited efficacy and potential risks. 1, 2

Adult Treatment Options

First-Line Treatment:

• Dextromethorphan (DM) - Centrally acting cough suppressant
  • Recommended dosage: 30 mg every 6-8 hours, not exceeding 120 mg in 24 hours 1
  • Available in extended-release formulations providing 12-hour relief 3
  • Shows modest effectiveness compared to placebo for reducing cough severity 2
  • Particularly useful for nighttime cough that disrupts sleep

Alternative Options:

• Glycerol-based cough syrups (e.g., Benylin, Robitussin for dry coughs)

  • May provide symptomatic relief for dry cough 4
  • Low cost and favorable side effect profile make them reasonable first attempts

• Butamirate citrate linctus (Sinecod syrup)

  • Has shown significant improvements in cough management 4
  • Not available in all countries

• Antihistamines

  • First-generation (sedating) antihistamines may be helpful for nocturnal cough 1
  • Non-sedating antihistamines like bilastine in combination with dextromethorphan have shown efficacy with less drowsiness 5

Children Treatment Options

First-Line Treatment:

• Honey (for children >1 year)
  • More effective than placebo or diphenhydramine 4
  • Comparable effectiveness to dextromethorphan 2
  • Do not use in infants under 1 year due to risk of botulism

Important Cautions for Children:

• OTC cough medications have little to no benefit for children 4, 6
• FDA warns against using OTC cough medications in children under 4 years 4
• Prescription opioid cough medicines should not be used in patients under 18 years 4
• Codeine-containing medications should be avoided due to potential for serious side effects including respiratory distress 4

Treatment Selection Based on Cough Type

For Dry, Non-Productive Cough:

• Antitussives (cough suppressants) like dextromethorphan 1, 7
• Goal: Suppress cough reflex

For Productive Cough with Mucus:

• Expectorants like guaifenesin 8
• Goal: Loosen phlegm and thin bronchial secretions to make coughs more productive
• Not recommended for dry cough

Important Considerations

Potential Side Effects:

• Dextromethorphan: Dizziness, mild sedation
• Antihistamine-containing preparations: Drowsiness, dry mouth, blurred vision
• Codeine and other opioid derivatives: Sedation, constipation, potential for dependence

When to Seek Medical Attention:

• If cough persists beyond 2 weeks
• If accompanied by concerning symptoms like hemoptysis, significant breathlessness, or prolonged fever 1
• If the patient has underlying respiratory or cardiac conditions

Treatment Limitations:

• Evidence for OTC cough medications is limited and results are variable 6
• Many studies show minimal differences compared to placebo, especially in children 2, 6
• Treatment should be targeted to the underlying cause when possible 9

Algorithmic Approach to Dry Cough Treatment

1. For adults with dry, irritating cough:

   • Start with dextromethorphan-containing products
   • If nighttime symptoms predominate, consider products with first-generation antihistamines
   • For daytime symptoms where alertness is needed, consider non-sedating formulations

2. For children with dry cough:

   • For children >1 year: Use honey
   • Avoid OTC cough medications in children under 4 years
   • For children 4-18 years: Use OTC medications with caution and only if benefits clearly outweigh risks

3. If no improvement after 1-2 weeks:

   • Evaluate for underlying causes (post-viral cough, asthma, GERD, post-nasal drip)
   • Consider medical consultation for persistent symptoms