What the label lists and what reports show
Chlorpheniramine and hydrocodone side effects
Chlorpheniramine and hydrocodone's FDA label: “The most common adverse reactions to Hydrocodone Polistirex and Chlorpheniramine Polistirex include: Sedation (somnolence, mental clouding, lethargy), impaired mental and physical performance, lightheadedness, dizziness, headache, dry mouth, nausea, vomiting …” FAERS holds 976 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is dependence (826 reports).
- Generic listed
- Boxed warning
- DEA Schedule II
Check it at the source: the chlorpheniramine and hydrocodone FDA label on DailyMed (effective June 26, 2025); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of Hydrocodone Polistirex and Chlorpheniramine Polistirex?Hydrocodone Polistirex and Chlorpheniramine Polistirex can cause serious side effects, including: See “ What is the most important information I should know about Hydrocodone Polistirex and Chlorpheniramine Polistirex?” Bowel problems including severe constipation or stomach pain. See “ Who should not take Hydrocodone Polistirex and Chlorpheniramine Polistirex?” Increased pressure in your head (intracranial). Avoid the use of Hydrocodone Polistirex and Chlorpheniramine Polistirex if you have a head injury or have been told that you have changes in the tissue of your brain (brain lesions) or increased pressure in your head. Increased risk of seizures in people with seizure disorders. If you have a seizure disorder, Hydrocodone Polistirex and Chlorpheniramine Polistirex may increase how often you have a seizure. Low blood pressure. […]
Source: FDA drug label, Bryant Ranch Prepack, effective June 26, 2025 (SPL set e0010aac-2d7e-4dd3-8024-ff0c7f668b77), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsThe most common adverse reactions to Hydrocodone Polistirex and Chlorpheniramine Polistirex include: Sedation (somnolence, mental clouding, lethargy), impaired mental and physical performance, lightheadedness, dizziness, headache, dry mouth, nausea, vomiting, and constipation.
From the label: adverse reactions, continuedThe following serious adverse reactions are described, or described in greater detail, in other sections: • Addiction, abuse, and misuse [ see Warnings and Precautions (5.1), Drug Abuse and Dependence (9.3) ] • Life-threatening respiratory depression [ see Warnings and Precautions (5.2 , 5.3 , 5.4 , 5.8 ), Overdosage (10) ] • Accidental overdose and death due to medication errors [ see Warnings and Precautions (5.5) ] • Decreased mental alertness with impaired mental and/or physical abilities [ see Warnings and Precautions (5.6) ] • Interactions with benzodiazepines and other CNS depressants [ see Warnings and Precautions (5.8), Drug Interactions (7.1 , 7.5 ) ] • Paralytic ileus, gastrointestinal adverse reactions [ see Warnings and Precautions (5.9) ] • Increased intracranial pressure [ see Warnings and Precautions (5.10 ) ] • Obscured clinical course in patients with head injuries [ see Warnings and Precautions (5.10) ] • Seizures [ see Warnings and Precautions (5.11) ] • Severe hypotension [ see Warnings and Precautions (5.12) ] • Neonatal Opioid Withdrawal Syndrome [ see Warnings and Precautions (5.13) ] • Adrenal insufficiency [ see Warnings and Precautions (5.14) ] The following adverse reactions have been identified during clinical studies, in the literature, or during post-approval use of hydrocodone and/or chlorpheniramine. …
Source: FDA drug label, Bryant Ranch Prepack, effective June 26, 2025 (SPL set e0010aac-2d7e-4dd3-8024-ff0c7f668b77), via openFDA; the full label on DailyMed
What do FAERS reports show?
976 reports list chlorpheniramine and hydrocodone among the medicines taken, each a report of something that happened, not proof the medicine caused it; 196 are coded as a death and 12 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 18 reactions below, 8 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Chlorpheniramine and hydrocodone: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions