evelops 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.
DRUG ABUSE AND DEPENDENCE:
This combination product is subject to the provisions of the Controlled Substance Act, and has been placed in Schedule III.
Dihydrocodeine can produce drug dependence of the codeine type and therefore has the potential of being abused.
Like other opioid analgesics, dihydrocodeine may produce subjective effects other than analgesia (e.g., euphoria, relaxation), which may contribute to abuse by some patients. Psychological dependence, physical dependence, and tolerance may develop upon repeated administration of dihydrocodeine, and It should be prescribed and administered with the same degree of caution appropriate to the use of other oral opioid analgesic medications.
Symptoms of dihydrocodeine withdrawal consist of irritability, restlessness, insomnia, diaphoresis, anxiety and palpitations.
Prolonged, high intake of caffeine may produce tolerance and habituation. Physical signs of withdrawal, such as headaches, irritation, nervousness, anxiety, and dizziness may occur upon abrupt discontinuation.
OVERDOSAGE:
Following an acute overdosage with Acetaminophen, caffeine, and dihydrocodeine bitartrate tablets, toxicity may result from the dihydrocodeine, acetaminophen, or, less likely, caffeine component. An overdose is a potentially lethal polydrug overdose situation, and consultation with a regional poison control center is recommended. A listing of the poison control centers can be found in standard references such as the Physician's Desk Reference®.
Signs and Symptoms and Laboratory Findings:
Toxicity from dihydrocodeine is typical of opioids and includes pinpoint pupils, respiratory depression, and loss of consciousness. Convulsions, cardiovascular collapse, and death may occur. A single case of acute rhabdomyolysis associated with an overdose of dihydrocodeine has been reported. With acetaminophen, dose-dependent potentially fatal
