How Long does Promethazine stay in your system

What is Promethazine and what is it used for

Promethazine is a first-generation antihistamine of the phenothiazine family. It is used to treat allergic reactions, reduce motion sickness and postoperative nausea. Promethazine is also sometimes mixed with codeine and dextromethorphan as a cough medication and also as a cure for insomnia in cases where benzodiazepines are contraindicated.

Recreational use and Side effects of Promethazine

Despite the various medicinal uses of promethazine, it can be used as a recreational drug. Both its medicinal use and recreational abuse can yield an array of unpleasant side effects. These include impaired cognitive functioning, confusion, general fatigue, drowsiness, dry mouth, akathisia, and paresthesia.

 Promethazine drug tests

Generally, you need not worry about promethazine showing up in a drug test as it is not a controlled substance and therefore, not looked for in the test. The only thing that you do need to bear in mind is that if the drug you took was with or without codeine, which is a drug that is looked for in drug tests.

How long does Promethazine stay in your system after your last dose

To ascertain how long promethazine will be in your system after you have taken the last dose, we must take into account the mode in which the drug was administered to you. There are various ways to get promethazine into your system, whether via an intravenous injection or an intramuscular injection. Other modalities include oral ingestion of the drug and the administration of promethazine through the rectum. Each route has a different time period required for the elimination of the drug.

Intravenous	Half-life of 9-16 hours	Elimination time around 2.06 to 3.67 days.
Intramuscular	Half-life of 9-16 hours	Elimination time is a little bit quicker than the intravenously administered variant.
Oral	Half-life – 16-19 hours	It will take 88 to 104.5 hours for orally ingested promethazine to be eliminated.
Rectal	Half-life – 16-19 hours	Similar elimination time as orally ingested promethazine, unclear which variant is cleared quicker, compared to each other.

We must remember that the time periods given above are an average estimation of the time necessary for promethazine elimination. Individual factors such as age, physical condition, body mass, genetics, hepatic and renal conditions, rate of metabolism as well as other factors like the dosage taken, frequency of administration and co-administration of other drugs, also have an effect on the elimination process.