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These brands contain the same active ingredient (Chlorpromazine Hydrochloride). Same strength and form. Confirm the switch with your doctor or pharmacist.
More from Largactil
Other strengths and forms by Synovia Pharma PLC.
Indications & Uses
Largactil is indicated for:
Pharmacology
Chlorpromazine works by blocking several different receptors on the nerve cells that receive messages in the brain and body. Its effects depend on which receptor it blocks.
On dopamine receptors (subtypes D1, D2, D3 and D4), it acts as an antipsychotic. This helps with both the productive symptoms (such as hallucinations and delusions) and the unproductive symptoms (such as withdrawal and flat emotions) of psychosis.
On serotonin receptors (5-HT1 and 5-HT2), it can ease anxiety, lift mood and reduce aggression. It also softens some extrapyramidal side effects. But the same blocking can cause weight gain, a fall in blood pressure, sedation and difficulty with ejaculation.
On histamine receptors (H1), it causes sedation and helps prevent vomiting. It can also bring on vertigo, a fall in blood pressure and weight gain.
On alpha1 and alpha2 receptors, it blocks the effects of adrenaline-like hormones. This lowers blood pressure, and the body may respond with a faster heartbeat (reflex tachycardia). Other effects include vertigo, sedation, excess saliva, incontinence and sexual problems. It may also reduce pseudoparkinsonism, although experts are not agreed on this.
On muscarinic (cholinergic) M1 and M2 receptors, it causes anticholinergic effects such as dry mouth, blurred vision, constipation, difficulty or inability to pass urine, a fast heartbeat (sinus tachycardia), ECG changes and memory loss. Blocking these receptors may, however, reduce some extrapyramidal side effects.
Chlorpromazine also weakly stops dopamine from being taken back into the nerve cell (reuptake), which may cause mild antidepressant and antiparkinsonian effects. The same action could in principle lead to psychomotor agitation and a worsening of psychosis, though this is very rarely seen in clinical use.
Dosage Reference
Reference Information Only
Dosages shown are general references from official sources. Always consult your doctor or pharmacist for personalized dosing.
Adults:
Adults, in general medicine and psychiatry, oral route: the average daily dose is 30 to 75 mg in mild cases, or 75 to 100 mg in more severe cases, given in divided doses. It is occasionally necessary to give a higher dosage, which, when increased gradually, can reach 900 mg or more per day in some psychiatric patients. Once the optimum dosage has been reached, it is maintained for as long as necessary to control symptoms during the critical phase of the illness. Eventually, however, it should be reduced gradually so the patient can be maintained on the lowest effective dosage.
Adults, in surgery and anesthesia, to potentiate hypnotics, analgesics and anesthetics, and as an antiemetic, oral route: doses of 25 to 50 mg are given 2 to 3 hours before anesthesia and every 4 to 6 hours after surgery.
Children: the usual single dose is 1/4 mg per pound (1/2 mg/kg) by oral route. This dose can be repeated every 4 to 6 hours as needed. The normal daily dose is 40 mg for a child of 5 years (40 pounds), and 75 mg for children aged 5 to 12 years (50 to 100 pounds), except in psychiatric patients, where dosages can be progressively increased above these levels. For surgery and anesthesia, the dose is 1/4 mg per pound, given by the same method recommended for adults.
Side Effects
Drowsiness often occurs when treatment begins but usually eases or fades once the dose is lowered. Orthostatic hypotension is also seen occasionally in the early stage of treatment, especially with high doses. Dystonic and extrapyramidal reactions can appear during prolonged treatment with elevated dosages, but these can be resolved by reducing the dose or giving an antiparkinsonian agent. Other side effects that occur less often include nasal congestion, blurred vision, dry mouth, sedation, nausea, constipation, changes in libido, gynecomastia, weight gain, pigmentation of the skin and cornea, photosensitivity, blood dyscrasias, leukopenia, eosinophilia and EEG changes. Very rare cases of QT interval prolongation have been reported. There have been isolated reports of sudden death, possibly of cardiac origin, as well as cases of unexplained sudden death in patients receiving neuroleptic phenothiazines. Cholestatic jaundice and liver injury, mainly of cholestatic or mixed type, are rarely reported in patients treated with Opsonil. Systemic lupus erythematosus has been reported very rarely in patients treated with Opsonil. In some cases, positive anti nuclear antibodies may be seen without evidence of clinical disease. Priapism has been reported very rarely in patients treated with Opsonil.
Cautions & Contraindications
Warnings & Precautions
Opsonil can intensify the effects of other phenothiazines and CNS depressants. When treatment begins, the usual doses of barbiturates, analgesics, narcotics, or antihistamines should be reduced by half. Patients should be warned against drinking alcohol while on Opsonil therapy. Neuroleptic phenothiazines may worsen QT interval prolongation, and this effect is more pronounced in the presence of bradycardia, hypokalemia, and congenital or acquired (e.g., drug-induced) QT prolongation. Opsonil should be used with caution in patients with arteriosclerosis, cardiovascular disease, or other conditions in which a sudden drop in blood pressure must be avoided. If hypotension does occur and a hypertensive agent is needed, norepinephrine should be used rather than epinephrine, since the latter can worsen hypotension. Because of its anticholinergic properties, Opsonil must also be used with caution in patients with glaucoma or prostatic hypertrophy. During prolonged therapy, particularly at high doses, blood counts and liver function tests should be performed at regular intervals. Drowsiness may occur early in treatment, so patients should be warned against driving or engaging in activities that require mental alertness until this effect has passed. Phenothiazines can trigger epileptic seizures by lowering the seizure threshold, so during Opsonil therapy, the patient's usual anticonvulsant medication should be continued at the same dose. Because of its antiemetic effect, Opsonil can mask symptoms of intracranial hypertension or intestinal obstruction. False positive or negative pregnancy test results have occurred in patients receiving phenothiazine therapy.
Contraindications
Contraindicated in patients with severe central nervous system depression or coma resulting from alcohol, barbiturates, analgesics, or other CNS depressants. It should also be avoided in patients with blood dyscrasias, severe liver disease, or known sensitivity to phenothiazines.
Pregnancy & Breastfeeding
Pregnancy category C. Animal studies using the oral route have shown reproductive toxicity, with dose related effects on the embryo and foetus, including increased resorptions and foetal deaths. A higher rate of malformations was seen in mice, but only at doses that were also toxic to the mother. Animal data on reproductive toxicity with the parenteral route are insufficient. In humans, the teratogenic risk of chlorpromazine has not been formally assessed. Various prospective epidemiological studies of other phenothiazines have produced conflicting findings on teratogenic risk. Chlorpromazine passes into breast milk in varying amounts, so it is not recommended for breastfeeding mothers unless the expected benefit is judged to outweigh any possible risk.
⚠️ Talk to your doctor before taking any medicine during pregnancy or while breastfeeding.
Use in Special Populations
Elderly
Older people are more likely to suffer the side effects of chlorpromazine. The starting dose should be about half the usual adult dose, and any increase should be made gradually and reviewed regularly.
Storage
Store Chlorpromazine Hydrochloride below 30°C, and keep it away from light and moisture. Keep it out of the reach of children.
Drug Interactions
Common questions about Largactil 50 mg
What is Largactil 50 mg Tablet?
Largactil 50 mg Tablet is a medicine that contains Chlorpromazine Hydrochloride. It is made by Synovia Pharma PLC. It belongs to the Anti-emetic drugs group of medicines.
What is Largactil used for?
Largactil is used for: Nausea and Vomiting, Anxiety, Schizophrenia, Bipolar Disorder.
What are the side effects of Largactil?
Drowsiness often occurs when treatment begins but usually eases or fades once the dose is lowered. Orthostatic hypotension is also seen occasionally in the early stage of treatment, especially with high doses.
Can I take Largactil during pregnancy or while breastfeeding?
Pregnancy category C. Animal studies using the oral route have shown reproductive toxicity, with dose related effects on the embryo and foetus, including increased resorptions and foetal deaths. Talk to your doctor before taking any medicine during pregnancy or while breastfeeding.
How should I store Largactil?
Store Chlorpromazine Hydrochloride below 30°C, and keep it away from light and moisture. Keep it out of the reach of children.
Can I take other medicines with Largactil?
Some medicines can interact with Chlorpromazine Hydrochloride, for example: Ciprofloxacin, Dextromethorphan + Phenylephrine + Triprolidine, Gliclazide, Nalidixic Acid, Suxamethonium Chloride, Insulin Detemir. Tell your doctor or pharmacist about every medicine you take.
Do I need a prescription for Largactil?
Largactil is a prescription (Rx) medicine. Take it as your doctor advises.