Meds & supplements › Dihydrocodeine
Medicine · Central Nervous System Stimulant
TREZIX™ (acetaminophen, caffeine, and dihydrocodeine bitartrate) capsulesare indicated for the relief of moderate to moderately severe pain.
Selected manufacturer label information, organised into consistent sections by Sofidex. This source is written for healthcare professionals; ask your pharmacist to explain instructions that are unclear. Read the full label at DailyMed ↗
Acetaminophen, caffeine, and dihydrocodeine bitartrate tablets are indicated for the relief of moderate to moderately severe pain.
The usual adult dosage is one (1) Acetaminophen, caffeine, and dihydrocodeine bitartrate tablets orally every four (4) hours, as needed. Dosage should be adjusted according to the severity of the pain and the response of the patient. No more than one (1) tablet should be taken in a 4-hour period. No more than five (5) doses, or five (5) tablets should be taken in a 24-hour period.
Dihydrocodeine:
The most frequently observed adverse reactions include light-headedness, dizziness, drowsiness, headache, fatigue, sedation, sweating, nausea, vomiting, constipation, pruritus, and skin reactions. With the exception of constipation, tolerance develops to most of these effects. Other reactions that have been observed with dihydrocodeine or other opioids include respiratory depression, orthostatic hypotension, cough suppression, confusion, diarrhea, miosis, abdominal pain, dry mouth, indigestion, anorexia, spasm of biliary tract, and urinary retention. Physical and psychological dependence are possibilities. Hypersensitivity reactions (including anaphylactoid reactions), hallucinations, vivid dreams, granulomatous interstitial nephritis, severe narcosis and acute renal failure have been reported rarely during dihydrocodeine administration.
Acetaminophen:
Acetaminophen in therapeutic doses rarely causes adverse reactions.
The most serious adverse reaction is hepatoxicity from overdosage (see OVERDOSAGE ). Thrombocytopenia, leukopenia, pancytopenia, neutropenia, thrombocytopenic purpura, and agranulocytosis have been reported in patients receiving acetaminophen or p-aminophenol derivatives. Hypersensitivity reactions including urticarial or erythematous skin reactions, laryngeal edema, angioedema, or anaphylactoid reactions are rare.
Caffeine:
Adverse reactions associated with caffeine use include anxiety, anxiety neurosis, excitement, headaches, insomnia, irritability, lightheadedness, restlessness, tenseness, tremor, extrasystoles, palpitations, tachycardia, diarrhea, nausea, stomach pain, vomiting, diuresis, urticarcia, scintillating scotoma, and tinnitus.
This combination product is contraindicated in persons with hypersensitivity to dihydrocodeine, codeine, acetaminophen, caffeine, or any of the inactive components listed above, or any situation where opioids are contraindicated including significant respiratory depression (in unmonitored settings or in the absence of resuscitative equipment), acute or severe bronchial asthma or hypercapnia, and paralytic ileus.
Dihydrocodeine with Other Central Nervous System Depressants:
Patients receiving other opioid analgesics, sedatives or hypnotics, muscle relaxants, general anesthetics, centrally acting anti-emetics, phenothiazines or other tranquilizers, or alcohol concomitantly with this combination product may exhibit additive depressant effects on the central nervous system. When such combined therapy is contemplated, the dose of one or both agents should be reduced.
Dihydrocodeine with Monoamine Oxidase Inhibitors:
Dihydrocodeine, like all opioid analgesics, interacts with monoamine oxidase inhibitors causing central nervous system excitation and hypertension.
Dihydrocodeine with Mixed Agonist/Antagonist Opioid Analgesics:
Agonist/antagonist analgesics (i.e., pentazocine, nalbuphine, butorphanol and buprenorphine) may reduce the analgesic effect of this combination product.
Acetaminophen-Drug Interactions:
Chronic and excessive consumption of alcohol may increase the hepatotoxic risk of acetaminophen. The potential for hepatotoxicity with acetaminophen also may be increased in patients receiving anticonvulsants that induce hepatic microsomal enzymes (including phenytoin, barbiturates, and carbamazepine) or isoniazide. Chronic ingestion of large doses of acetaminophen may slightly potentiate the effects of warfarin- and indandione- derivative anticoagulants. Severe hypothermia is possible in patients receiving acetaminophen concomitantly with phenothiazines.
Caffeine-Drug Interactions:
Caffeine may enhance the cardiac inotropic effects of beta-adrenergic stimulating agents. Coadministration of caffeine and disulfiram may lead to a substantial decrease in caffeine clearance. Caffeine may increase the metabolism of other drugs such as phenobarbital and aspirin. Caffeine accumulation may occur when products or foods containing caffeine are consumed concomitantly with quinolones such as ciprofloxacin.
Selection of patients for treatment with Acetaminophen, caffeine, and dihydrocodeine bitartrate tablets should be governed by the same principles that apply to the use of similar opioid/non-opioid fixed combination analgesics. As with any such opioid analgesic, the dosing regimen should be adjusted for each patient (see DOSAGE AND ADMINISTRATION ). This combination product should be used with caution in elderly or debilitated patients or those with any of the following conditions: acute alcoholism; adrenocortical insufficiency (e.g., Addison's disease); asthma; central nervous system depression or coma; chronic obstructive pulmonary disease; decreased respiratory reserve (including emphysema, severe obesity, cor pulmonale, or kyphoscoliosis); delirium tremens; head injury; hypotension; increased intracranial pressure; myxedema or hypothyroidism; prostatic hypertrophy or urethral stricture; and toxic psychosis. The benefits and risks of using opioids in patients taking monoamine oxidase inhibitors and in those with a history of drug abuse should be carefully considered. The administration of an analgesic containing an opioid may obscure the diagnosis or clinical course in patients with acute abdominal conditions. This combination product may aggravate convulsions in patients with convulsive disorders and, like all opioids, may induce or aggravate seizures in some clinical settings. Acetaminophen is relatively non-toxic at therapeutic doses, but should be used with caution in patients with severe renal or hepatic disease. Care should be observed when using large doses of acetaminophen in malnourished patients or those with a history of chronic alcohol abuse because they may be more susceptible to hepatic damage similar to that observed with toxic overdosage.
Caffeine in high doses may produce central nervous system and cardiovascular stimulation and gastrointestinal irritation.
sofidex [Internet]. Daloreum; c2026. Dihydrocodeine; [reviewed 2026 Aug 2; cited 2026 Nov 10]. Available from: https://sofidex.com/patients/medicines/dihydrocodeine
sofidex. (2026, August 2). Dihydrocodeine. Daloreum. Retrieved November 10, 2026, from https://sofidex.com/patients/medicines/dihydrocodeine
Dihydrocodeine. sofidex. Reviewed August 2, 2026. Accessed November 10, 2026. https://sofidex.com/patients/medicines/dihydrocodeine
The cited date is today’s, because a citation records when you read the page. The reviewed date is when a clinician last checked it.