| Amoxapine Pharmacology |
| Amoxapine |
| About Amoxapine |
| Dibenzoxazepine class, Anti depressent. |
| Mechanism of Action of Amoxapine |
| Amoxapine acts by inhibiting the re-uptake of Noradrenaline, and Serotonin (5 HT) in the CNS nerve terminals .This will result in an increased concentration of neurotransmitters in the synaptic cleft and produces antidepressant effect. Amoxapine also blocks the response of Dopamine receptor to Dopamine.8-Hydroxyamoxapine; the metabolite of Amoxapine more selectively inhibits the reuptake of Serotonin than Noradrenaline. 7-Hydroxyamoxapine has Dopamine receptor blocking activity. |
| Pharmacokinets of Amoxapine |
| Absorption: Amoxapine is rapidly absorbed after oral administration. Distribution: It is widely distributed in the body in protein bound form Metabolism: Amoxapine is metabolised in the liver to active metabolites 8-Hydroxyamoxapine and 7-Hydroxyamoxapine. Excretion: Drug is excreted mainly through urine. Some is excreted through faeces also. |
| Onset of Action for Amoxapine |
| 2 days |
| Duration of Action for Amoxapine |
| 4 – 7 days |
| Half Life of Amoxapine |
| 8 – 30 hours |
| Side Effects of Amoxapine |
| 1. Drowsiness 2 Dizziness 3. Nausea 4. Vomiting 5. Blurred vision 6. Difficulty in micturition 7. Tachycardia 8. Hypotension 10. Dryness of mouth 11. Constipation 12. Confusion 13. Headache 14. Sedation 15. Blood dyscrasias 16. Tardive dyskinesia 17. Rash 18. Jaundice 19. Anorexia 20. Impotence 21. Loss of libido 22. Galactorrhea 23. Gynecomastia |
| Contra-indications of Amoxapine |
| 1. Hypersensitivity to Amoxapine 2. Myocardial infarction 3. Severe liver disease |
| Special Precautions while taking Amoxapine |
| 1.Renal impairment 2.Hepatic impairment 3.Cardiac arrhythmia 4.Myocardial infarction 5.Tachycardia 6.Heart failure 7.Strokes 8.Angle closure glaucoma 9.History of urine retention 10.Hyperthyroidism 11.Epilepsy 12. Alcoholics 13.Slowly withdraw the drug with caution 14.Patient should be cautioned against driving vehicle, operating machine and activities requiring mental alertness or judgment. |
| Pregnancy Related Information |
| Contraindicated. |
| Old Age Related Information |
| Use with caution. |
| Breast Feeding Related Information |
| Contraindicated |
| Children Related Information |
| Contraindicated |
| Indications for Amoxapine |
| 1.Depression 2.Obsessive compulsive disorder |
| Interactions for Amoxapine |
| Anticholinergics: Enhanced effect of anticholinergics may occur. Barbiturates: Serum level of imipramine decreased; additive respiratory depressant effect. Clonidine: Hypertensive crisis. Dicoumarol: Increase in anticoagulation effects. Disulfiram: Acute organic brain syndrome. Fluoxetine & Haloperidol: Potentiate action of Amoxapine. Levodopa: Its bioavailability is reduced, hypertensive episodes. MAOIs Furazolidone: Seizures, sweating , coma, hyperexcitability, hyperthermia, tachycardia, mydriasis, confusion, DIC (Disseminated Intravascular Coagulation) and death. Oral contraceptives and phenothiazines: Increase plasma levels of Amoxapine. Smoking: Increases metabolic bio-transformation. Alcohol: Sedative effective of alcohol potentiated. |
| Typical Dosage for Amoxapine |
| Adult: Initial dose: 100- 150 mg / day at night or in 2 -3 divided doses. Dose can be gradually increases up to 300 mg / day in 2 – 3 divided doses. Maintenance dose: 150 – 250 mg / day in 2 – 3 divided doses or as single dose at night. Maximum dose: 600 mg / day |
| Schedule of Amoxapine |
| H |
| Storage Requirements for Amoxapine |
| Store in a cool place in a tightly closed container. Keep out of the reach of children. |
| Effects of Missed Dosage of Amoxapine |
| Take the missed dose as soon as noticed and if it is the time to take the next dose then skip the missed dose. |
| Effects of Overdose of Amoxapine |
| Give supportive measures and treatment. Remove the drug from the body by inducing emesis and by gastric lavage. Charcoal is given to reduce the absorption of the drug. Seizure can be treated with Diazepam or Phenytoin, arrhythmia with Lidocaine and acidosis with Sodium bicarbonate. |