Dura-vent/a

Dura-vent/a Uses, Dosage, Side Effects, Food Interaction and all others data.

Chlorpheniramine is an alkylamine antihistamine. It is one of the most potent H1 blocking agents and is generally effective in relatively low doses. Chlorpheniramine is not so prone to produce drowsiness, readily absorbed from the gastro-intestinal tract, metabolised in the liver and excreted usually mainly as metabolised in the urine.

In allergic reactions an allergen interacts with and cross-links surface IgE antibodies on mast cells and basophils. Once the mast cell-antibody-antigen complex is formed, a complex series of events occurs that eventually leads to cell-degranulation and the release of histamine (and other chemical mediators) from the mast cell or basophil. Once released, histamine can react with local or widespread tissues through histamine receptors. Histamine, acting on H1-receptors, produces pruritis, vasodilatation, hypotension, flushing, headache, tachycardia, and bronchoconstriction. Histamine also increases vascular permeability and potentiates pain. Chlorpheniramine, is a histamine H1 antagonist (or more correctly, an inverse histamine agonist) of the alkylamine class. It competes with histamine for the normal H1-receptor sites on effector cells of the gastrointestinal tract, blood vessels and respiratory tract. It provides effective, temporary relief of sneezing, watery and itchy eyes, and runny nose due to hay fever and other upper respiratory allergies.

Phenylpropanolamine is a sympathomimetic agent that acts as a nonselective adrenergic receptor agonist and norepinephrine reuptake inhibitor. It has been used as a decongestant and appetite suppressant. Currently, it is withdrawn from the market in Canada and the United States due to the risk for hemorrahgic strokes.

Phenylpropanolamine (PPA), a sympathomimetic agent structurally similar to pseudoephedrine, is used to treat nasal congestion. Phenylpropanolamine is found in appetite suppressant formulations and with guaifenesinin in cough-cold formulations. In 2000, the FDA requested that all drug companies discontinue marketing products containing phenylpropanolamine, due to an increased risk of hemorrhagic stroke in women who used phenylpropanolamine.

Dura-vent/a
Uses
Dosage
Side Effect
Precautions
Interactions
Uses during Pregnancy
Uses during Breastfeeding
Accute Overdose
Food Interaction
Half Life
Volume of Distribution
Clearance
Interaction With other Medicine
Contradiction
Storage

Trade Name	Dura-vent/a
Generic	Chlorpheniramine + Phenylpropanolamine
Type
Therapeutic Class
Manufacturer
Available Country	United States
Last Updated:	September 19, 2023 at 7:00 am

Uses

Indicated mainly in allergic conditions including urticaria, sensitivity reactions, angioneurotic oedema, seasonal hay fever, vasomotor rhinitis, cough, common cold, motion sickness.

Phenylpropanolamine is a sympathomimetic that was previously used in nasal decongestants and weight loss products, but has been withdrawn by the FDA due to safety risks and lack of efficacy.

For the treatment of nasal congestion, control of urinary incontinence, priapism and obesity.

Dura-vent/a is also used to associated treatment for these conditions: Allergic Contact Dermatitis, Allergic Reaction, Allergic Rhinitis (AR), Allergic cough, Allergies, Allergies caused by Serum, Allergy to House Dust, Allergy to vaccine, Angioneurotic Edema, Asthma, Bronchial Asthma, Bronchitis, Common Cold, Conjunctival congestion, Conjunctivitis, Conjunctivitis allergic, Cough, Cough caused by Common Cold, Coughing caused by Flu caused by Influenza, Drug Allergy, Eye allergy, Fever, Flu caused by Influenza, Food Allergy, Headache, Headache caused by Allergies, Itching of the nose, Itching of the throat, Migraine, Nasal Congestion, Nasal Congestion caused by Common Cold, Pollen Allergy, Productive cough, Pruritus, Rash, Rhinorrhoea, Seasonal Allergic Conjunctivitis, Sinus Congestion, Sinusitis, Sneezing, Transfusion Reactions, Upper Respiratory Tract Infection, Upper respiratory tract hypersensitivity reaction, site unspecified, Urticaria, Vasomotor Rhinitis, Acute Rhinitis, Allergic purpura, Conjunctival hyperemia, Dry cough, Excess mucus or phlegm, Itchy throat, Mild bacterial upper respiratory tract infections, Ocular hyperemia, Throat inflammation, Upper airway congestion, Upper respiratory symptoms, Watery eyes, Watery itchy eyes, Airway secretion clearance therapyAllergy-Induced Respiratory Symptoms, Bronchitis, Common Cold, Cough, Nasal Congestion, Rhinorrhoea, Excess mucus or phlegm

How Dura-vent/a works

Chlorpheniramine binds to the histamine H1 receptor. This blocks the action of endogenous histamine, which subsequently leads to temporary relief of the negative symptoms brought on by histamine.

Phenylpropanolamine acts directly on alpha- and, to a lesser degree, beta-adrenergic receptors in the mucosa of the respiratory tract. Stimulation of alpha-adrenergic receptors produces vasoconstriction, reduces tissue hyperemia, edema, and nasal congestion, and increases nasal airway patency. PPA indirectly stimulates beta-receptors, producing tachycardia and a positive inotropic effect.

Dosage

Dura-vent/a dosage

Adults: 4 mg 3-4 times daily.

Children:

Up to 1( one) year: 1 mg twice daily
1-5 years: 1 mg 3-4 times daily
6-12 years: 2 mg 3-4 times daily or as directed by the physician

Side Effects

Drowsiness, dizziness, headache, psychomotor impairment, urinary retention, dry mouth, blurred vision and gastro intestinal disturbances, paradoxical stimulation may rarely occur, especially in high dosage or in children.

Toxicity

Oral LD50 (rat): 306 mg/kg; Oral LD50 (mice): 130 mg/kg; Oral LD50 (guinea pig): 198 mg/kg [Registry of Toxic Effects of Chemical Substances. Ed. D. Sweet, US Dept. of Health & Human Services: Cincinatti, 2010.] Also a mild reproductive toxin to women of childbearing age.

May induce ventricular extrasystoles and short paroxysms of ventricular tachycardia, a sensation of fullness in the head and tingling of the extremities; LD₅₀=1490mg/kg (orally in rat)

Precaution

Chlorpheniramine may produce mild sedation and it is advised that patients under continuous treatment should avoid operating machinery. Not recommended during pregnancy & lactation.

Interaction

Alcohol, CNS depressants, anticholinergic drugs, MAOIs.

Elimination Route

Well absorbed in the gastrointestinal tract.

Reduced bioavailability (about 38%) from gastrointestinal tract because of first pass metabolism by monoamine oxidase in the stomach and liver.

Half Life

21-27 hours

2.1 to 3.4 hours.

Pregnancy & Breastfeeding use

Pregnancy Category B. Either animal-reproduction studies have not demonstrated a foetal risk but there are no controlled studies in pregnant women or animal-reproduction studies have shown an adverse effect (other than a decrease in fertility) that was not confirmed in controlled studies in women in the 1st trimester (and there is no evidence of a risk in later trimesters).

Contraindication

There is no definite contraindication to therapy. It should be used with caution in epilepsy, prostatic hypertrophy, glaucoma and hepatic disease. The ability to drive or operate machinery may be impaired.