COMPOSITION: Each mL of sterile solution contains:
Promethazine Hydrochloride
25 mg
Sodium Metabisulphite
0,1% m/v
Sodium Sulphite
0,1% m/v
Ascorbic Acid
0,2% m/v
PHARMACOLOGICAL CLASSIFICATION: A 2.6.1 Phenothiazine and derivatives.
PHARMACOLOGICAL ACTION. Promethazine hydrochloride is a phenothiazine histamine antagonist and has anticholinergic, sedative, antiserotoninergic, anti-emetic and local anaesthetic properties.
INDICATIONS: Promethazine is indicated in disorders known to respond to antihistamine therapy. It is used for the palliation of allergic reactions, as an anti-emetic for motion sickness, as a sedative and as an anti-tussive. Larger doses have been given for control of Parkinsonian symptoms, e.g. oculogyric crises.
CONTRA-INDICATIONS: It must be used with caution in patients with hepatic diseases. Promethazine hydrochloride may enhance the sedative effect of central nervous system depressants including barbiturates, hypnotics, narcotic analgesics, sedatives and tranquilizers. It must be used with care in patients receiving the above medications.
WARNINGS: Promethazine may cause drowsiness and dulling of mental alertness, which may be aggravated by simultaneous intake of alcohol or other central nervous system depressant agents. Patients undergoing treatment with promethazine should not take charge of vehicles or other means of transport, or machinery where loss of attention may lead to accidents.
DOSAGE AND DIRECTIONS FOR USE: 20 mg to 50 mg daily by the intramuscular route.
25 mg to 100 mg intramuscularly for anaesthetic premedication.
SIDE-EFFECTS AND SPECIAL PRECAUTIONS: The most common effect, is sedation varying from slight drowsiness to deep sleep and including inability to concentrate, lassitude, dizziness, hypotension, muscular weakness and ataxia. Tightness of the chest and tingling, heaviness and weakness of hands may occur.
Other side-effects include gastro-intestinal disturbances such as nausea, vomiting, diarrhoea or constipation, colic and epigastric pain, as well as headache, tinnitus, elation and depression, irritability, nightmares, anorexia, difficulty in micturition, dryness of the mouth. Large doses may precipitate fits in epileptics. Blood dyscrasias including agranulocytosis and haemolytic anaemia, though rare, have been reported. Allergic reactions and anaphylaxis may occur.
In infants and children it may act as a cerebral stimulant. Symptoms of stimulation in adults include insomnia, nervousness, tachycardia, tremors, muscle twitching and convulsions.
Promethazine has anticholinergic properties and should be used with care in conditions such as glaucoma and prostatic hypertrophy. The anticholinergic effects of atropine and tricyclic antidepressants may be enhanced by Promethazine.
It may mask the warning symptoms of damage caused by ototoxic medicines and may affect the metabolism of other medicines in the liver. It may enhance the sedative effect of central nervous system depressants including alcohol, barbiturates, hypnotics, narcotic analgesics, sedatives and tranquillizers.
Promethazine hydrochloride should be used cautiously in patients with hepatic disease. Intravenous injections of promethazine hydrochloride must be given slowly and extreme care must be taken to avoid perivascular extravasation or inadvertent intra-arterial injection, due to the risk of severe chemical irritation.
KNOWN SYMPTOMS OF OVERDOSAGE AND PARTICULARS OF ITS TREATMENT: The chief symptom of acute poisoning from the ingestion of promethazine hydrochloride is unconsciousness. In addition, excitement, agitation, mental confusion and convulsion have occurred with unconsciousness intervening between spasms.
If it has been taken recently by mouth, the stomach should be emptied by aspiration and lavage. Emetics are generally of little value. The patient should be kept quiet, to minimize the excitation which occurs particularly in children. Convulsion and central nervous system stimulation should be treated with diazepam or phenobarbitone intramuscularly. Care must be taken in the administration of sedatives, as they may be enhanced by promethazine.
Severe hypotension may require fluid replacement and assisted respiration may be necessary.
The administration of antibiotics as a prophylactic against pneumonia should be considered.
Treatment of other manifestations is symptomatic and supportive.
IDENTIFICATION: A clear colourless to slightly straw coloured solution.
PRESENTATION: 1 mL and 2 mL amber ampoules, packed in boxes containing 10’s and 100’s.
STORAGE INSTRUCTIONS: Store below 25°C. Protect from light
KEEP OUT OF REACH OF CHILDREN
INTRAMED PROMETHAZINE HYDROCHLORIDE INJECTION 25 mg