Each tablet contains:
Prochlorperazine Maleate 5 mg
Prochlorperazine has a wide range of activity arising from its depressant
actions on the central nervous system and its alpha-adrenergic blocking and
weaker anti-cholinergic activities. It is a dopamine inhibitor, it inhibits
prolactin-release inhibitory factor, considered to be dopamine, thus
stimulating the release of prolactin. The turnover of dopamine in the brain
is also increased. Prochlorperazine possesses sedative and tranquilising
properties but patients usually develop tolerance rapidly to the sedation.
It has anti-emetic, anti-pruritic and weak anti-histamine properties and
inhibit the heat regulating centre so that the patient tends to acquire the
temperature of his surroundings. Prochlorperazine produces direct effects on
the heart and blood vessels and also indirect ones through actions on CNS
and autonomic reflexes. Hypotension is primarily due to inhibition of
centrally mediated pressor effects but peripheral alpha-adrenergic blockage
may also play a role. There is also a direct depressant action on the heart.
The drug has a vasodilating action due to both its effects on the autonomic
nervous system and a direct action on blood vessels.
Prochlorperazine is well absorbed from the gastrointestinal tract. From 60
to 70% of an administered dose is rapidly removed from the portal
circulation by the liver and there is a very active enterohepatic
circulation. Fecal excretion of prochlorperazine is significant. A
reciprocal relationship exists between the amounts excreted in the faeces
and the urine. After absorption, it is rapidly distributed in all body
tissues. Brain concentrations are relatively low compared to those in other
organs, but considerably higher than in plasma; the highest concentrations
of the drug is found in the lung, followed by the liver, the adrenal gland,
and the spleen.
For control of severe nausea and vomiting and treatment of non-psychotic
It is contraindicated in greatly depressed states due to central nervous
system depressants and in the presence of bone marrow depression.
It is also contraindicated in children under 2 years of age or under 9 kg
in weight. It should not be used in children for conditions for which dosage
has not been established.
Side effects / adverse reactions
Drowsiness, dizziness, amenorrhea, blurred vision, skin reactions and
hypotension may occur.
Cholestatic jaundice has occurred. Leukopenia and agranulocytosis have also
Neuromuscular reactions characterised by motor restlessness, be of the
dystonic type or may resemble parkinsonism are observed. Symptoms of motor
restlessness may include agitation, jitteriness and sometimes insomnia.
Symptoms of dystonia may include spasm of the neck muscles, sometimes
progressing to torticollis; extensor rigidity of back muscles, sometimes
progressing to opisthotonos; carpopedal spasm, trismus, swallowing
difficulty, oculogyric crisis and protrusion of the tongue. Symptoms of
pseudo-parkinsonism may include mask-like facies; drooling; tremors;
pillrolling motion; cogwheel rigidity and shuffling gait. As with all
antipsychotic agents, tardive dyskinesia may appear in some patients on long
term therapy. This condition appears in all age groups. However, the risk
appears to be greater in elderly patients on high dose therapy, especially
females. The symptoms are persistent and in some patients appear to be
irreversible. The syndrome is characterised by rhythmical involuntary
movements of the tongue, face, mouth or jaw. Sometimes these may be
accompanied by involuntary movements of extremities.
Precautions / Warnings
The extrapyramidal symptoms which can occur secondary to prochlorperazine
may be confused with the central nervous system signs of an undiagnosed
primary disease responsible for the vomiting, e.g. Reye's syndrome or other
encephalopathy. The use of prochlorperazine and other potential hepatotoxins
should be avoided in children and adolescents whose signs and symptoms
suggest Reye's syndrome.
When prochlorperazine is used with cancer chemotherapeutic drugs, vomiting
as a sign of the toxicity of these agents may be obscured by the antiemetic
effect of prochlorperazine. Phenothiazines can diminish the effect of oral
Thiazide diuretics may accentuate the orthostatic hypotension that may
occur with phenothiazines. Antihypertensive effects of guanethidine and
related compounds may be counteracted when phenothiazines are used
Concomitant administration of propranolol with phenothiazines results in
increased plasma levels of both drugs.
Patients with bone marrow depression or who have previously demonstrated
a hypersensitivity reaction (e.g., blood dyscrasias, jaundice) with a
phenothiazine should not receive any phenothiazine, including
prochlorperazine, unless in the judgement of the physician the potential
benefits of treatment outweigh the possible hazards.
Prochlorperazine may impair mental and/or physical abilities, especially
during the first few days of therapy. Therefore, caution patients about
activities requiring alertness (e.g. operating vehicles or machinery).
The antiemetic action of prochlorperazine may mask the signs and symptoms
of overdosage of other drugs and may obscure the diagnosis and treatment of
other conditions such as intestinal obstruction, brain tumor and Reye's
Aspiration of vomitus
has occurred in a few post-surgical patients who have received
prochlorperazine as an antiemetic. Although no causal relationship has been
established, this possibility should be borne in mind during surgical
As with all drugs which exert an anticholinergic effect and/or cause
mydriasis, prochlorperazine should be used with caution in patients with
Because phenothiazines may interfere with thermoregulatory mechanisms, use
with caution in persons who will be exposed to extreme heat.
Phenothiazines can produce alpha-adrenergic blockade.
The presence of phenothiazines may produce false-positive phenylketonuria (PKU)