What is the recommended dosing for Cheratussin AC (hydrocodone and guaifenesin)?

Cheratussin AC Dosing

Cheratussin AC (hydrocodone-guaifenesin combination) should be dosed at 5-10 mL every 4-6 hours as needed for adults, with a maximum of 6 doses per 24 hours, ensuring total daily hydrocodone does not exceed 60 mg (60 MME/day) and total acetaminophen from all sources remains below 4,000 mg. 1

Adult Dosing Guidelines

Standard dosing for hydrocodone-containing cough preparations:

• Initial dose: 5-10 mL (containing approximately 5-10 mg hydrocodone) every 4-6 hours as needed 1
• Maximum frequency: Every 4 hours, up to 6 times daily 2
• Daily hydrocodone limit: 60 mg/day (equivalent to 60 MME), which approaches the 50 MME/day threshold requiring heightened monitoring 1, 3

Guaifenesin component considerations:

• Typical formulations contain 100-200 mg guaifenesin per 5 mL 2
• Therapeutic guaifenesin dosing range: 200-400 mg every 4 hours, up to 6 times daily 2
• Extended-release formulations allow 12-hourly dosing but are not applicable to liquid Cheratussin AC 4

Critical Safety Parameters

Opioid-specific precautions:

• Prescribe "as needed" rather than scheduled dosing to minimize opioid exposure 1
• Start opioid-naïve patients at the lowest effective dose (5-10 MME per single dose or 20-30 MME/day) 1, 3
• Duration should be limited to 3-7 days for acute cough from upper respiratory infections 1
• Check prescription drug monitoring program (PDMP) before prescribing 1

Hydrocodone conversion factor:

• 1 mg hydrocodone = 1 MME (morphine milligram equivalent) 3
• Doses ≥50 MME/day require careful reassessment of benefits versus risks 3

Special Population Adjustments

Elderly patients (≥65 years):

• Require dose reduction due to smaller therapeutic window between safe dosages and respiratory depression 5
• Consider starting with lower doses (5 mg hydrocodone equivalent per dose) 5
• Monitor closely for sedation and respiratory depression 5

Pediatric dosing (ages 2-17 years):

• Age-based guaifenesin doses: 100-400 mg based on age and weight 6
• Hydrocodone-containing products generally avoided in children under 18 years due to respiratory depression risk
• Allometric scaling shows no maturation-related changes in guaifenesin clearance 6

Clinical Context for Appropriate Use

Cheratussin AC should only be prescribed when:

• Nonopioid cough suppressants (dextromethorphan, benzonatate) have failed 1
• Cough is severe enough to significantly impair quality of life or sleep
• Expected duration of severe cough is limited (typically 3-7 days) 1

Guaifenesin mechanism:

• Acts as expectorant by loosening mucus and making coughs more productive 2
• Inhibits cough reflex sensitivity in patients with upper respiratory tract infections 7
• Requires multiple daily doses to maintain 24-hour therapeutic effect with immediate-release formulations 2

Common Pitfalls to Avoid

Do not:

• Prescribe as first-line therapy when nonopioid alternatives may be effective 1
• Use scheduled dosing instead of as-needed administration 1
• Exceed 60 mg hydrocodone daily without careful risk-benefit reassessment 1, 3
• Combine with other acetaminophen-containing products if formulation includes acetaminophen 1
• Prescribe for chronic cough without addressing underlying etiology

Monitor for:

• Respiratory depression, particularly in elderly patients and those with sleep apnea 5
• Sedation and altered mental status 5
• Constipation (consider prophylactic laxatives for prolonged use) 5
• Drug interactions, especially with other CNS depressants 5

Practical Dosing Algorithm

For acute cough from upper respiratory infection:

1. Start with 5 mL (approximately 5 mg hydrocodone) every 4-6 hours as needed 1
2. May increase to 10 mL per dose if inadequate response after 24-48 hours 1
3. Limit total daily doses to 6 or fewer 2
4. Reassess need after 3-5 days; discontinue if cough improving 1
5. Do not exceed 7 days of therapy for acute conditions 1