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Details

Stereochemistry RACEMIC
Molecular Formula C17H20N2S.C4H4O4
Molecular Weight 400.491
Optical Activity ( + / - )
Defined Stereocenters 0 / 1
E/Z Centers 1
Charge 0
Stereo Comments C17H20N2S

SHOW SMILES / InChI
Structure of PROMETHAZINE MALEATE

SMILES

OC(=O)\C=C/C(O)=O.CC(CN1C2=C(SC3=C1C=CC=C3)C=CC=C2)N(C)C

InChI

InChIKey=JSYGKADGBBTFIQ-BTJKTKAUSA-N
InChI=1S/C17H20N2S.C4H4O4/c1-13(18(2)3)12-19-14-8-4-6-10-16(14)20-17-11-7-5-9-15(17)19;5-3(6)1-2-4(7)8/h4-11,13H,12H2,1-3H3;1-2H,(H,5,6)(H,7,8)/b;2-1-

HIDE SMILES / InChI

Description

Promethazine is a phenothiazine derivative with histamine H1-blocking, antimuscarinic, and sedative properties. Promethazine HCl Oral Solution is useful for: perennial and seasonal allergic rhinitis. Allergic conjunctivitis due to inhalant allergens and foods. Anaphylactic reactions, as adjunctive therapy to epinephrine and other standard measures, after the acute manifestations have been controlled. Preoperative, postoperative, or obstetric sedation. Prevention and control of nausea and vomiting associated with certain types of anesthesia and surgery. Therapy adjunctive to meperidine or other analgesics for control of post-operative pain. Active and prophylactic treatment of motion sickness. Antiemetic therapy in postoperative patients.

CNS Activity

Originator

Approval Year

Targets

Primary TargetPharmacologyConditionPotency

Conditions

ConditionModalityTargetsHighest PhaseProduct
Primary
PROMETHAZINE HYDROCHLORIDE
Primary
PROMETHAZINE HYDROCHLORIDE
Primary
PROMETHAZINE HYDROCHLORIDE
Preventing
PROMETHAZINE HYDROCHLORIDE
Primary
PROMETHAZINE HYDROCHLORIDE

Cmax

ValueDoseCo-administeredAnalytePopulation
13.2 ng/mL
25 mg single, oral
PROMETHAZINE blood
Homo sapiens
10 ng/mL
12.5 mg single, intravenous
PROMETHAZINE blood
Homo sapiens
11.28 ng/mL
50 mg single, rectal
PROMETHAZINE plasma
Homo sapiens
21.84 ng/mL
50 mg single, oral
PROMETHAZINE plasma
Homo sapiens
48.26 ng/mL
50 mg single, intramuscular
PROMETHAZINE plasma
Homo sapiens
5.75 ng/mL
25 mg single, rectal
PROMETHAZINE plasma
Homo sapiens
19.3 ng/mL
50 mg single, oral
PROMETHAZINE plasma
Homo sapiens
9.04 ng/mL
50 mg single, rectal
PROMETHAZINE plasma
Homo sapiens

AUC

ValueDoseCo-administeredAnalytePopulation
11511 ng × h/mL
25 mg single, oral
PROMETHAZINE blood
Homo sapiens
14466 ng × h/mL
12.5 mg single, intravenous
PROMETHAZINE blood
Homo sapiens
146.62 ng × h/mL
50 mg single, rectal
PROMETHAZINE plasma
Homo sapiens
180.14 ng × h/mL
50 mg single, oral
PROMETHAZINE plasma
Homo sapiens
627.13 ng × h/mL
50 mg single, intramuscular
PROMETHAZINE plasma
Homo sapiens
146 ng × h/mL
25 mg single, rectal
PROMETHAZINE plasma
Homo sapiens
361 ng × h/mL
50 mg single, oral
PROMETHAZINE plasma
Homo sapiens
256 ng × h/mL
50 mg single, rectal
PROMETHAZINE plasma
Homo sapiens

T1/2

ValueDoseCo-administeredAnalytePopulation
12.2 h
12.5 mg single, intravenous
PROMETHAZINE blood
Homo sapiens
17.7 h
25 mg single, rectal
PROMETHAZINE plasma
Homo sapiens
18.6 h
50 mg single, oral
PROMETHAZINE plasma
Homo sapiens
17.2 h
50 mg single, rectal
PROMETHAZINE plasma
Homo sapiens

Doses

AEs

OverviewOther

Other InhibitorOther SubstrateOther Inducer

Drug as perpetrator​

Drug as victim

Tox targets

PubMed

Sample Use Guides

In Vivo Use Guide
Allergy: the average oral dose is 25 mg taken before retiring; however, 12.5 mg may be taken before meals and on retiring, if necessary. Single 25 mg doses at bedtime or 6.25 to 12.5 mg taken three times daily will usually suffice. After initiation of treatment in children or adults, dosage should be adjusted to the smallest amount adequate to relieve symptoms. The administration of promethazine HCI in 25 mg doses will control minor transfusion reactions of an allergic nature. Motion Sickness: the average adult dose is 25 mg taken twice daily. The initial dose should be taken one-half to one hour before anticipated travel and be repeated 8 to 12 hours later, if necessary. On succeeding days of travel, it is recommended that 25 mg be taken on arising and again before the evening meal. For children, 12.5 to 25 mg, twice daily, may be administered. Nausea and Vomiting: antiemetics should not be used in vomiting of unknown etiology in children and adolescents. The average effective dose of Promethazine HCL Oral Solution for the active therapy of nausea and vomiting in children or adults is 25 mg. When oral medication cannot be tolerated, the dose should be given parenterally or by rectal suppository. 12.5 to 25 mg doses may be repeated, as necessary, at 4 to 6 hour intervals. For nausea and vomiting in children, the usual dose is 0.5 mg per pound of body weight, and the dose should be adjusted to the age and weight of the patient and the severity of the condition being treated. For prophylaxis of nausea and vomiting, as during surgery and the postoperative period, the average dose is 25 mg repeated at 4 to 6 hour intervals, as necessary. Sedation: this product relieves apprehension and induces a quiet sleep from which the patient can be easily aroused. Administration of 12.5 to 25 mg Promethazine HCl Oral Solution by the oral route will provide sedation in children. Adults usually require 25 to 50 mg for nighttime, presurgical, or obstetrical sedation. Pre- and Postoperative Use: promethazine HCl Oral Solution in 12.5 to 25 mg doses for children and 50 mg doses for adults the night before surgery relieves apprehension and produces a quiet sleep. For preoperative medication, children require doses of 0.5 mg per pound of body weight in combination with an appropriately reduced dose of narcotic or barbiturate and the appropriate dose of an atropine-like drug. Usual adult dosage is 50 mg Promethazine HCl Oral Solution with an appropriately reduced dose of narcotic or barbiturate and the required amount of a belladonna alkaloid. Postoperative sedation and adjunctive use with analgesics may be obtained by the administration of 12.5 to 25 mg in children and 25 to 50 mg doses in adults. Promethazine HCL Oral Solution is contraindicated for children under 2 years of age.
Route of Administration: Oral
In Vitro Use Guide
Unknown