Drug Information

  



       












Pharmacokinetics

 


Flupenthixol is readily
absorbed from the gastrointestinal tract and is probably subject to
first-pass metabolism in the gut wall. It is also extensively
metabolised in the liver and is excreted in the urine and faeces in the
form of numerous metabolites; there is evidence of enterohepatic
recycling. Owing to the first-pass effect, plasma concentrations
following oral administration are much lower than those following
estimated equivalent doses of the intramuscular depot preparation.
Moreover, there is very wide intersubject variation in plasma
concentrations of flupenthixol, but in practice, no simple correlation
has been found between plasma concentrations of flupenthixol and its
metabolites, and the therapeutic effect. Paths of metabolism of
flupenthixol include sulphoxidation, side-chain N-dealkylation, and
glucuronic acid conjugation. It is widely distributed in the body, and
crosses the blood-brain barrier. Flupenthixol passes the placental
barrier and small amounts have been detected in breast milk.



The decanoate ester of flupenthixol is very slowly absorbed from the
site of intramuscular injection and is therefore suitable for depot
injection. It is gradually released into the blood stream where it is
rapidly hydrolysed to flupenthixol.

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Indication
& Dosage


 

Oral


SCHIZOPHRENIA AND RELATED PSYCHOTIC CONDITIONS:
Initially 3-9mg b.i.d.,
adjusted according to response. Max 18mg/day DEPRESSIONS, PSYCHOSOMATIC
DISORDERS 0.5mg b.i.d. Increase upto 3-5mg daily. Elderly: Start at half
the adult dose and increase gradually.

Children: not recommended

IM

MAINTENANCE IN SCHIZOPHRENIA AND OTHER PSYCHOSES:
20-40MG DEEP IM as
depot injection every 2-4 weeks

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Action



Flupenthixol exerts its
neuroleptic effect by mixed blockade of dopamine d1 and d2 receptors in
the limbic system (antipsychotic effects) and the striatal system (extrpyramidal
effects). Increases prolactin secretion (hypothalamic action) and has
antiemetic action. Flupenthixol produces calmness and reposiveness.
Aggressive behaviour is reduced while hallucinations and delusions
disappear. Has antidepressant effect.

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Interaction

The most
common interactions encountered with phenothiazines are adverse effects
resulting from concomitant administration of drugs with similar
pharmacological actions. When given with other drugs that produce
orthostatic hypotension dosage adjustments may be necessary. However, it
should be noted that phenothiazines have been reported to reduce the
antihypertensive action of guanethidine and other adrenergic neurone
blockers. As many phenothiazines possess antimuscarinic actions they may
potentiate the adverse effects of other drugs with antimuscarinic
actions, including tricyclic antidepressants and the antimuscarinic
antiparkinsonian drugs that may be given to treat phenothiazine-induced
extrapyramidal effects. In theory, antipsychotics with dopamine-blocking
activity and dopaminergic drugs such as those used to treat parkinsonism
may be mutually antagonistic. Concomitant administration of
metoclopramide may increase the risk of antipsychotic-induced
extrapyramidal effects.

There is an
increased risk of arrhythmias when antipsychotics are used with drugs
which prolong the QT interval including certain antiarrhythmics,
antihistamines, antimalarials, and cisapride. There is also an increased
risk of arrhythmia when tricyclic antidepressants are used with
antipsychotics which prolong the QT interval. Because of an increased
risk of seizures the US manufacturers recommend discontinuation of
chlorpromazine before the use of metrizamide for radiographic
procedures. Symptoms of CNS depression may be enhanced by other drugs
with CNS-depressant properties including alcohol, general anaesthetics,
hypnotics, anxiolytics, and opioids.

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Adverse
Effect & Precaution




Neuroleptic Malignant
Syndrome, nausea epigastric distress, dyskinesia and restlessness.



Precaution: Severe hepatic, cardiac and renal disease. With other CNS
depressants and ethanol. Epilepsy and has to be tapered off gradually.

Pregnancy: Contraindicated.

Breast Feeding: Contraindicated.

Man: May be given in reduced dose

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Brands
available in market


 














 

 

 

 

FLUANXOL

 

 

CFL

TAB

0.5mg

10

14.68

TAB

1mg

10

25.56

TAB

3mg

10

67.05

FLUANXOL DEPOT

 

 

CFL

INJ

20mg

1ml

76.09

INJ

40mg

2ml

147.42


Top

   



 






 

       

   
Drug Information
  

       

Pharmacokinetics
 
Flupenthixol is readily absorbed from the gastrointestinal tract and is probably subject to first-pass metabolism in the gut wall. It is also extensively metabolised in the liver and is excreted in the urine and faeces in the form of numerous metabolites; there is evidence of enterohepatic recycling. Owing to the first-pass effect, plasma concentrations following oral administration are much lower than those following estimated equivalent doses of the intramuscular depot preparation. Moreover, there is very wide intersubject variation in plasma concentrations of flupenthixol, but in practice, no simple correlation has been found between plasma concentrations of flupenthixol and its metabolites, and the therapeutic effect. Paths of metabolism of flupenthixol include sulphoxidation, side-chain N-dealkylation, and glucuronic acid conjugation. It is widely distributed in the body, and crosses the blood-brain barrier. Flupenthixol passes the placental barrier and small amounts have been detected in breast milk.

The decanoate ester of flupenthixol is very slowly absorbed from the site of intramuscular injection and is therefore suitable for depot injection. It is gradually released into the blood stream where it is rapidly hydrolysed to flupenthixol.

Top
    

Indication & Dosage
 
Oral
SCHIZOPHRENIA AND RELATED PSYCHOTIC CONDITIONS: Initially 3-9mg b.i.d., adjusted according to response. Max 18mg/day DEPRESSIONS, PSYCHOSOMATIC DISORDERS 0.5mg b.i.d. Increase upto 3-5mg daily. Elderly: Start at half the adult dose and increase gradually.
Children: not recommended

IM
MAINTENANCE IN SCHIZOPHRENIA AND OTHER PSYCHOSES:
20-40MG DEEP IM as depot injection every 2-4 weeks

Top
    

Action

Flupenthixol exerts its neuroleptic effect by mixed blockade of dopamine d1 and d2 receptors in the limbic system (antipsychotic effects) and the striatal system (extrpyramidal effects). Increases prolactin secretion (hypothalamic action) and has antiemetic action. Flupenthixol produces calmness and reposiveness. Aggressive behaviour is reduced while hallucinations and delusions disappear. Has antidepressant effect.

Top
   

Interaction

The most common interactions encountered with phenothiazines are adverse effects resulting from concomitant administration of drugs with similar pharmacological actions. When given with other drugs that produce orthostatic hypotension dosage adjustments may be necessary. However, it should be noted that phenothiazines have been reported to reduce the antihypertensive action of guanethidine and other adrenergic neurone blockers. As many phenothiazines possess antimuscarinic actions they may potentiate the adverse effects of other drugs with antimuscarinic actions, including tricyclic antidepressants and the antimuscarinic antiparkinsonian drugs that may be given to treat phenothiazine-induced extrapyramidal effects. In theory, antipsychotics with dopamine-blocking activity and dopaminergic drugs such as those used to treat parkinsonism may be mutually antagonistic. Concomitant administration of metoclopramide may increase the risk of antipsychotic-induced extrapyramidal effects.

There is an increased risk of arrhythmias when antipsychotics are used with drugs which prolong the QT interval including certain antiarrhythmics, antihistamines, antimalarials, and cisapride. There is also an increased risk of arrhythmia when tricyclic antidepressants are used with antipsychotics which prolong the QT interval. Because of an increased risk of seizures the US manufacturers recommend discontinuation of chlorpromazine before the use of metrizamide for radiographic procedures. Symptoms of CNS depression may be enhanced by other drugs with CNS-depressant properties including alcohol, general anaesthetics, hypnotics, anxiolytics, and opioids.

Top
   

Adverse Effect & Precaution

Neuroleptic Malignant Syndrome, nausea epigastric distress, dyskinesia and restlessness.

Precaution: Severe hepatic, cardiac and renal disease. With other CNS depressants and ethanol. Epilepsy and has to be tapered off gradually.
Pregnancy: Contraindicated.
Breast Feeding: Contraindicated.
Man: May be given in reduced dose

Top
    

 

 

 

 

FLUANXOL

 

 

CFL

TAB

0.5mg

10

14.68

TAB

1mg

10

25.56

TAB

3mg

10

67.05

FLUANXOL DEPOT

 

 

CFL

INJ

20mg

1ml

76.09

INJ

40mg

2ml

147.42

Top
   

 

 

By |2022-07-20T16:42:52+00:00July 20, 2022|Uncategorized|Comments Off on Flupenthixol

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