butalbital + acetaminophen + caffeine + codeine phosphate

**Butalbital + acetaminophen + caffeine + codeine phosphate** is an oral fixed-dose, four-component analgesic product for management of the symptom complex of tension or muscle-contraction headache when non-opioid analgesics and alternative treatments are inadequate. It combines butalbital, a barbiturate central nervous system depressant; acetaminophen, a non-opioid analgesic; caffeine, a methylxanthine stimulant; and codeine phosphate, an opioid agonist. Butalbital enhances inhibitory GABA-A signaling and may inhibit AMPA-mediated excitatory neurotransmission; caffeine antagonizes adenosine receptors; and codeine provides opioid analgesia primarily through mu-opioid receptor activity, including after metabolic conversion to morphine. The precise analgesic mechanism of acetaminophen is not fully established. The product is supplied as an oral capsule, is classified in the United States as Schedule III, and carries boxed warnings for addiction, abuse, misuse, respiratory depression, and acetaminophen-associated hepatotoxicity. ([dailymed.nlm.nih.gov](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=52321fe5-c001-4e2d-8149-3197ddc13764))

Brand names

Fioricet with CodeinePhrenilin with Caffeine and Codeine

Other names

acetaminophen + butalbital + caffeine + codeine phosphatebutalbital + acetaminophen + caffeine + codeine