Tussionex Liquid Composition
Tussionex is an extended-release oral suspension containing hydrocodone polistirex (an opioid antitussive) and chlorpheniramine polistirex (a first-generation antihistamine) in a liquid vehicle designed for sustained drug release over 12 hours.
Active Pharmaceutical Ingredients
The liquid formulation contains two active components in polistirex form (a polymer-bound complex that provides extended release):
- Hydrocodone polistirex - An opioid agonist that acts centrally to suppress cough 1
- Chlorpheniramine polistirex - A first-generation antihistamine with anticholinergic properties that helps control upper respiratory symptoms 2, 3
Mechanism and Formulation Design
The polistirex delivery system is critical to understanding this medication:
- The suspension vehicle allows the active drugs to be bound to an ion-exchange resin polymer, creating a sustained-release effect 4
- This formulation is designed for dosing every 12 hours, unlike immediate-release combinations that require dosing every 4-6 hours 1, 4
- The liquid suspension must be shaken well before use to ensure uniform distribution of the drug-resin complexes
Clinical Context
Hydrocodone is recognized as an effective antitussive agent, particularly for cancer-related cough, with demonstrated efficacy in dose-titration studies showing median 70% reduction in cough frequency 1. However, recent evidence has raised significant concerns about pediatric use 5.
The chlorpheniramine component provides additional benefit through:
- Anticholinergic effects that control rhinorrhea better than second-generation antihistamines 2
- Sedating properties that may be valuable when cough disturbs sleep 3
Important Safety Considerations
- This is a Schedule III controlled substance due to the hydrocodone content 1
- The extended-release formulation should only be used in opioid-tolerant patients, not for acute new-onset symptoms 1
- First-generation antihistamines like chlorpheniramine can cause performance impairment and sedation with prolonged plasma half-life (approximately 21.6 hours) 2, 4
- The FDA has determined that hydrocodone-containing cough medications should not be used in patients under 18 years due to unfavorable benefit-risk profile 5