Skip to content


  • by

Review about promethazine hydrochloride (hcl), We explain everything about promethazine: dosing, pregnancy, warnings, uses (for sleep, for anxiety) and formats (syrup ip, injection, im).

Welcome to my channel subscribe to learn more about the active ingredients of the medicines today we will talk about the mechanism of action side effects dosage interactions and warnings of permettez een what is per methos een promethazine is a phenothiazine that however has no neuroleptic effects it is an h1 antihistamine with anticholinergic sedative and antifungal

Effects with weak local anesthetic activity it is mainly used to prevent dizziness associated with boat or air travel and as an antiemetic mechanism of action the predominant action of promethazine is the antagonism of the h1 receptors although promethazine is classified as a phenothiazine its ability to antagonize dopamine is about 1/10 that of chlorpromazine

For this reason promethazine is not used as a neuroleptic like other h1 antagonists promethazine does not prevent histamine release as do chromatic 8 and the dock rimmel but it competes with free histamine for binding at h1 receptor sites histamine receptors in the gastrointestinal tract uterus blood vessels and bronchial muscle are blocked by promethazine relief

Of movement associated disease as well as nausea / vomiting appears to be related to central and the cholinergic actions and may involve activity at the meta larry site of chemo receptor activation other cns receptors may also be affected as per methylene indirectly reduces stimuli to the brain stem reticular system sedation is significant at achieved therapeutic

Dose concentrations the mild antitussive activity of promethazine probably results from anticholinergic and sedative actions local anesthetic activity requires higher concentrations than those required to antagonize histamine receptors pharmacokinetics promethazine is administered orally rectally intramuscularly and intravenously onset of action occurs within 15

To 60 minutes after hour allure rectal administration and within 20 minutes after intramuscular admitted raishin after intravenous administration onset of action occurs within three to five minutes and the histamine and sedative effects are maintained for four to six hours and two to eight hours respectively promethazine binds extensively to plasma proteins it is

Widely distributed in body tissues and fluids and it crosses the placenta and is excreted in breast milk metabolism takes place in the liver with production of inactive metabolites such as promethazine sulf oxide and other glue cure nights the elimination half-life is 10 to 14 hours with excretion of the metabolites in urine and feces toxicity no long-term studies

Have been conducted to evaluate the carcinogenic potential of promethazine nor have there been any published reports on its toxicity reproductive effects or fertility promethazine is not mutagenic in the aims salmonella test indications and pathology prevention of kinetic dizziness oral or rectal administration adults 25 milligrams p o or prairie 30 – 60 minutes

Before departure then every 12 hours as needed children over two years half a milligram kg maximum 25 milligrams p o or prairie 30 – 60 minutes before departure then every 12 hours as needed the usual dose for children is 12.5 to 25 milligrams treatment of nausea / vomiting oral rectal intramuscular or intravenous adult 12.5 to 25 milligrams every 4 to 6 hours as

Needed children over two years 0.25 to half a milligram / kg maximum 25 milligrams / dose every 4 to 6 hours as needed the average effective dose is 25 milligrams treatment of allergic manifestations oral or rectal administration adults the average dose is 25 milligrams p o or pr before bedtime however doses of 25 milligrams p o or p r can be administered for

Meals and before bedtime if necessary administration of 25 milligrams per methos een is sufficient to control allergic reactions that may occur in a transfusion children over two years six point two five to twelve point five milligrams bo or pr three times a day and before bed if necessary the maximum dose usually at bedtime is twenty five milligrams for induction

Of post-operative sedation as the supplement to angle g’s –ax oral intramuscular or intravenous administration adults twenty-five to fifty milligrams p o in more for in the single dose children over two years 12.5 to twenty-five milligrams p o m or four in one dose for the relief of apprehension and to induce quiet sleep from which the patient can be easily

Awakened oral rectal or intramuscular or intravenous dose of ministry ssin adults twenty-five to fifty milligrams p o pr in more for before bedtime children over two years twelve point five to 25 milligrams p o pr in more for before bedtime for obstetrics sedation intramuscular or intravenous administration adults twenty-five to fifty milligrams in more for during

The early stages of labor and 25 to 75 milligrams once labor is established repeat every two to four hours as needed patients with kidney failure no guidelines are available for dose adjustments in kidney failure but it appears that no adjustments are required contraindications and precautions promethazine should not be used in patients less than two years of age

Because it can cause respiratory depression that can be fatal fatalities have been reported with permettez e news and children under two years of age precautions should be taken when giving promethazine to children over two years of age the lowest possible doses should be used in concomitant use with other respiratory depressant drugs should be avoided phenothiazine

Derivatives lower the seizure threshold through their effect gavi therefore promethazine should be avoided if possible in patients with a seizure disorder were those receiving anticonvulsants the anticholinergic activity of h1 antagonists may result in a thickening of bronchial secretions in the airways aggravating an acute asthma or copd attack because promethazine

Has significant anticholinergic activity it should be avoided in those patients who have experienced a worsening of their respiratory status due to treatment with an h1 and agonist fda classification of risk in pregnancy promethazine is classified in pregnancy risk category c in general h1 antagonists are not recommended for use in pregnancy especially during

The third trimester because of their risk to the fetus because there are no adequate studies and pregnant women promethazine should be considered during pregnancy only if the benefits of treatment outweigh the risks to the fetus h1 antagonists are not recommended for use during lactation as they may induce paradoxical cns stimulation and newborns or seizures and

Preterm infants breastfeeding inhibition may also occur alternative feeding methods should be used if promethazine therapy is necessary promethazine should be used with caution and children because paradoxical cns stimulation may occur there have been a number of cases of respiratory depression and sleep apnea and children who received phenothiazine antihistamines

The mechanism of this reaction is not yet known therefore promethazine should be used with extreme caution in any case in children with a family history of sudden death or sleep apnea h1 antagonists should not be used in newborns because of the possibility of paradoxical cns stimulation or seizures promethazine should be avoided if possible in patients with open

Angle or closed angle glaucoma and the use of an h1 antagonist with less anticholinergic effects is advised increased intraocular pressure may occur due to the anticholinergic effects of the drug precipitating an acute glaucoma attack elderly patients are more susceptible to the anticholinergic effects of promethazine including possible precipitation of undiagnosed

Glaucoma other effects resulting from the iv cholinergic effects of promethazine include dry eyes or blurred vision this may be important in the elderly and contact lens wearers promethazine has important anticholinergic effects and a worsening of symptoms may be seen in patients with bladder obstruction gastro intestinal obstruction or alias benign prostatic

Hypertrophy or urinary retention the elderly are more susceptible to the anticholinergic effects of drugs as there is a decrease in endogenous cholinergic activity that occurs with h promethazine is metabolized extensively in the liver and its metabolism may be reduced in the presence of liver failure patients with liver disease should be closely monitored and dose

Adjustments may be necessary finaiiy azim should not be administered to patients treated with metra’s amide radiological contrast because of a possible increased risk of seizures finaiiy azim should be discontinued 48 hours before milah griffie and should not be resumed until 24 to 48 hours after the procedure promethazine may cause drowsiness patients who received

Promethazine should be advised to avoid driving or operating machinery until they know the effects of the drug interactions fanaa thea scenes inhibit and reverse the vasopressor effect of epinephrine therefore if necessary in a patient who has received promethazine and requires a vasopressor agent norepinephrine should be used the anticholinergic activity of meo

Is minimal although anticholinergic effects sometimes occur it is recommended that tummie life should not be used simultaneously with drugs that have anticholinergic activity especially atropine and scopolamine as their effects and those of other and the cholinergic drugs are potentiated and can become severe most authors recommend that antihistamines should not

Be used within 2 weeks before or after treatment with an maoi depending on the specific agent additive anticholinergic may be seen when drugs with antimuscarinic properties are used concomitant li the following drugs that possess antimuscarinic properties and should be used with caution are atropine and other similar anti mascara nix some h1 blockers for example

Carbon oxen clemmie steen diphenhydramine met dela zine promethazine try improvin some finale isn’t eg metazine promazine thioridazine dry fluid promazine some tricyclic antidepressants eg amitriptyline amok subpoena clomipramine pro trip tulane and other drugs with substantial antimuscarinic properties such as clozapine cyclobenzaprine and dye so pure mind drugs

With lesser degree of anticholinergic effects include amantadine bupropion chlorpromazine doxepin imipramine inappro– deline nortriptyline procainamide and trim amin physicians should note that antimuscarinic effects can be seen not only on gastrointestinal smooth muscle but also affect bladder eye and temperature regulation function because promethazine causes

Pronounced sedation and additive cns depressant effect may occur when it is combined with other cns depressants including ethanol barbiturates anxiolytics sedatives hypnotics and fanaa thousand opioid agonists butte orphan all now beyou fionn fantasy scene drama doll or other h1 blockers you

Transcribed from video