DOXYLAMINE

Absorption

Readily absorbed via the gastrointestinal tract.

Toxicity

Signs of overdose include wheezing, tightness in the chest, fever, itching, bad cough, blue skin color, fits, swelling of face, lips, tongue, or throat.

The Uses of DOXYLAMINE

(±)-Doxylamine is an intermediate in the synthesis of Doxylamine N, N’-Dioxide (D562025), which is an impurity of Doxylamine (succinate salt, D562000), which is an H1 Histamine receptor antagonist.

The Uses of DOXYLAMINE

Antihistaminic.

Background

Histamine H1 antagonist with pronounced sedative properties. It is used in allergies and as an antitussive, antiemetic, and hypnotic. Doxylamine has also been administered in veterinary applications and was formerly used in parkinsonism.

Indications

Used alone as a short-term sleep aid, in combination with other drugs as a night-time cold and allergy relief drug. Also used in combination with Vitamin B6 (pyridoxine) to prevent morning sickness in pregnant women.

Definition

ChEBI: Doxylamine is a member of pyridines and a tertiary amine. It has a role as a histamine antagonist, a cholinergic antagonist, a sedative, an antiemetic, a H1-receptor antagonist, an anti-allergic agent and an antitussive.

brand name

Decapryn (Sanofi Aventis); Unisom (Pfizer).

General Description

Clear colorless liquid.

Reactivity Profile

DOXYLAMINE is an amine. Amines are chemical bases. They neutralize acids to form salts plus water. These acid-base reactions are exothermic. The amount of heat that is evolved per mole of amine in a neutralization is largely independent of the strength of the amine as a base. Amines may be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen is generated by amines in combination with strong reducing agents, such as hydrides

Pharmacokinetics

Doxylamine is an antihistamine commonly used as a sleep aid. This drug is also used to relieve symptoms of hay fever (allergic rhinitis), hives (rash or itching), and other allergic reactions. Doxylamine is a member of the ethanolamine class of antihistamines and has anti-allergy power far superior to virtually every other antihistamine on the market, with the exception of diphenhydramine (Benadryl). It is also the most powerful over-the-counter sedative available in the United States, and more sedating than many prescription hypnotics. In a study, it was found to be superior to even the barbiturate, phenobarbital for use as a sedative. Doxylamine is also a potent anticholinergic.

Synthesis

Doxylamine is synthesized from phenyl-2- pyridinylmethyl carbinol and dimethylaminoethyl chloride in the presence of NaNH2 in xylene . It exhibits pronounced sedative effects. Therefore, doxylamine is mainly used as a sedative, a sleeping aid.

Metabolism

Hepatic.