COMPOSITION: Each DOLOXENE CO-65 capsule contains:
(equivalent to 65 mg propoxyphene hydrochloride)
Propoxyphene napsylate is a synthetic, odourless, white crystalline powder with a bitter taste. It is very slightly soluble in water and soluble in methanol, ethanol, chloroform and acetone. Chemically, it is alpha-(+)-4-(dimethylamino)-3-methyl-1,2 diphenyl-2-butanol propionate (ester) 2-naphthalene-sulphonate (salt) hydrate. It is structurally related to methadone.
PHARMACOLOGICAL CLASSIFICATION: A 2.8 Analgesic combinations
PHARMACOLOGICAL ACTION: Propoxyphene napsylate is a mild analgesic structurally related to the narcotic analgesic, methadone. Though propoxyphenes general pharmacological properties are those of the narcotics as a group, it does not compare with them in analgesic potency. Because of differences in molecular mass, a dose of 100 mg of propoxyphene napsylate is required to supply an amount of propoxyphene equivalent to that present in 65 mg propoxyphene hydrochloride.
The combination of propoxyphene with aspirin produces greater analgesia than that produced by either drug administered alone.
INDICATIONS: For the relief of mild to moderate pain.
CONTRA-INDICATIONS: DOLOXENE CO-65 is contra-indicated in patients with a known hypersensitivity to propoxyphene, aspirin or caffeine. Not to be taken during pregnancy.
Alcohol and central nervous system depressants should not be taken with dextropropoxyphene.
WARNINGS: Aspirin has been implicated in Reyes syndrome, a rare but serious illness, in children and teenagers with chickenpox and influenza. A doctor should be consulted before aspirin is used in such patients. Drug dependence: Care should be taken in prescribing this drug to persons susceptible to drug dependence. Propoxyphene can produce drug dependence characterised by psychic dependence and, less frequently, physical dependence and tolerance.
Propoxyphene will only partially suppress the withdrawal syndrome in individuals physically dependent on morphine or other narcotics. The abuse liability of propoxyphene is qualitatively similar to that of codeine although quantitatively less, and propoxyphene should be prescribed with the same degree of caution appropriate to the use of codeine. Usage in ambulatory patients: Propoxyphene may impair the mental and/or physical abilities required for the performance of potentially hazardous tasks, such as driving a car or operating machinery. The patient should be cautioned accordingly. Usage in pregnancy: Safe use in pregnancy has not been established relative to possible adverse effects on foetal development.
Instances of withdrawal symptoms in the neonate have been reported following usage during pregnancy. Therefore, propoxyphene should not be used in pregnant women unless, in the judgement of the physician, the potential benefits outweigh the possible hazards. Usage in children: Propoxyphene is not recommended for use in children because documented clinical experience has been insufficient to establish safety and suitable dosage regimen in the paediatric age group. CNS additive effects and overdosage: Propoxyphene napsylate in combination with alcohol, tranquillizers, sedative-hypnotics and other central nervous system depressants has additive depressant effects, and the patient should be so advised.
Patients taking this drug should be warned not to exceed the dosage recommended by their physician. Toxic effects and fatalities have occurred following overdoses of propoxyphene napsylate alone and in combination with other central nervous system depressants. The majority of these patients have histories of emotional disturbances or suicidal ideation or attempts as well as histories of misuse of tranquillizers, alcohol, or other CNS-active drugs. Caution should be exercised in prescribing unnecessarily large amounts of propoxyphene napsylate for such patients.. (See KNOWN SYMPTOMS OF OVERDOSAGE).
Do not use continuously for more than 10 days without consulting a doctor.
DOSAGE AND DIRECTIONS FOR USE: The usual adult dose is one capsule (containing 100 mg propoxyphene napsylate, 375 mg aspirin and 30 mg caffeine) every 4 hours as needed for pain.
SIDE EFFECTS AND SPECIAL PRECAUTIONS: The most frequent side effects are dizziness, sedation, nausea and vomiting. These effects seem to be more prominent in ambulatory than in non-ambulatory patients, and some of these adverse reactions may be alleviated if the patient lies down.
Other adverse reactions include constipation, abdominal pain, skin rashes, light-headedness, headache, weakness, euphoria, dysphoria and minor visual disturbances. The chronic ingestion of propoxyphene in doses exceeding 800 mg per day has caused toxic psychoses and convulsions. A single dose of 1200 mg of propoxyphene napsylate has caused convulsions. Hepatotoxicity can occur. Salicylates should be used with extreme caution in the presence of peptic ulcer or coagulation abnormalities.
Confusion, anxiety and tremors have been reported in a few patients receiving propoxyphene concomitantly with orphenadrine.
The central nervous system depressant effect of propoxyphene may be additive with that of other CNS depressants, including alcohol. (See WARNINGS).
Salicylates may enhance the effect of anticoagulants and inhibit the uricosuric effect of uricosuric agents.
KNOWN SYMPTOMS OF OVERDOSAGE AND PARTICULARS OF ITS TREATMENT:
Symptoms: The manifestations of serious overdosage with propoxyphene are similar to those of narcotic overdosage and include respiratory depression (a decrease in respiratory rate and/or tidal volume, Cheyne-Stokes respiration, cyanosis), extreme somnolence progressing to stupor or coma, pupillary constriction and circulatory collapse. Overdoses of propoxyphene can cause delay of cardiac conduction as well as focal or generalised convulsions.
In addition to these characteristics typical of narcotic poisoning, focal and generalised convulsions constitute a prominent feature in most cases of severe propoxyphene poisoning and cardiac arrhythmias and pulmonary oedema have occasionally been reported. Apnoea, cardiac arrest and death have occurred. When propoxyphene napsylate with aspirin has been ingested, the clinical picture may be complicated by salicylism. Treatment: Primary attention should be given to the re-establishment of adequate respiratory exchange through provision of patent airway and institution of assisted or controlled ventilation. The narcotic antagonists, naloxone, levallorphan and nalorphine are specific antidotes against the respiratory depression produced by an overdose of propoxyphene. An appropriate dose of one of these antagonists should be administered preferably by the intravenous route, simultaneously with efforts at respiratory resuscitation, and the antagonist should be repeated as necessary until the patients condition remains satisfactory. In addition to the use of a narcotic antagonist, the patient may require careful titration with an anticonvulsant to control convulsions. Analeptic drugs (for example, caffeine or amphetamine) should not be used because of their tendency to precipitate convulsions.
Oxygen, intravenous fluid, vasopressors, and other supportive measures should be employed as indicated.
Gastric lavage may be helpful. Activated charcoal can adsorb a significant amount of ingested propoxyphene. Dialysis is of little value in poisoning by propoxyphene alone.
IDENTIFICATION: DOLOXENE CO-65 capsule is a size 0 capsule with an opaque grey cap and an opaque red body.
PRESENTATION: DOLOXENE CO-65 capsules are supplied in blister packs of 20 and 100.
STORAGE INSTRUCTIONS: Store below 30°C in blister packs.
KEEP OUT OF REACH OF CHILDREN.
REFERENCE NUMBER: B584 (Act 101/1965)
NAME AND BUSINESS ADDRESS OF THE APPLICANT: Pharmacare Limited
7 Fairclough Road
DATE OF PUBLICATION OF THIS PACKAGE INSERT: 28 October 1969
252787 - 02/02
Updated on this site: October 2004
Source: Community Pharmacy