A decongestant or nasal decongestant is a type of drug A drug, broadly speaking, is any substance that, when absorbed into the body of a living organism, alters normal bodily function. There is no single, precise definition, as there are different meanings in drug control law, government regulations, medicine, and colloquial usage which is used to relieve nasal congestion Nasal congestion is the blockage of the nasal passages usually due to membranes lining the nose becoming swollen from inflamed blood vessels. It is also known as nasal blockage, nasal obstruction, blocked nose, runny nose, stuffy nose, or stuffed up nose.
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Pharmacology
The vast majority of decongestants act via enhancing norepinephrine Noradrenaline (abbreviated NA or NAd) or norepinephrine (INN) (abbreviated norepi or NE) is a catecholamine with dual roles as a hormone and a neurotransmitter (noradrenaline) and epinephrine Epinephrine is a hormone and neurotransmitter. When produced in the body it increases heart rate, contracts blood vessels and dilates air passages and participates in the "fight or flight" response of the sympathetic nervous system. It is a catecholamine, a sympathomimetic monoamine produced only by the adrenal glands from the amino (adrenaline) or adrenergic activity by stimulating the α-adrenergic receptors The adrenergic receptors are a class of G protein-coupled receptors that are targets of the catecholamines, especially noradrenaline (norepinephrine) and adrenaline (epinephrine). Although dopamine is a catecholamine, its receptors are in a different category. This induces vasoconstriction Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, particularly the large arteries, small arterioles and veins. The process is the opposite of vasodilation, the widening of blood vessels. The process is particularly important in staunching hemorrhage and acute blood loss. When of the blood vessels The blood vessels are the part of the circulatory system that transport blood throughout the body. There are three major types of blood vessels: the arteries, which carry the blood away from the heart, the capillaries, which enable the actual exchange of water and chemicals between the blood and the tissues; and the veins, which carry blood from in the nose Anatomically, a nose is a protuberance in vertebrates that houses the nostrils, or nares, which admit and expel air for respiration in conjunction with the mouth. Behind the nose is the olfactory mucosa and the sinuses. Behind the nasal cavity, air next passes through the pharynx, shared with the digestive system, and then into the rest of the, throat In anatomy, the throat is the anterior part of the neck, in front of the vertebral column. It consists of the pharynx and larynx. An important feature of the throat is the epiglottis, a flap which separates the esophagus from the trachea and prevents inhalation of food or drink, and paranasal sinuses Paranasal sinuses form developmentally through excavation of bone by air-filled sacs from the nasal cavity. This process begins prenatally, and it continues through the course of an organism's lifetime, which results in reduced inflammation Inflammation is the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli as well as initiate the healing process for the tissue. Inflammation is not a synonym for infection. Even in cases where (swelling In medical parlance, swelling is the enlargement of organs caused by accumulation of excess fluid in tissues, called edema) and mucus In vertebrates, mucus is a slippery secretion produced by, and covering, mucous membranes. It is a viscous colloid containing antiseptic enzymes , proteines such as lactoferrin, glycoproteins and immunoglobulins that serves to protect epithelial cells in the respiratory, gastrointestinal, urogenital, visual, and auditory systems in mammals; the formation in these areas.
The active ingredients in most ingested decongestants are pseudoephedrine Pseudoephedrine [pronunciation: so͞oˌdō-ĭ-fĕdˈrĭn or so͞oˌdō-ĕfˈĭ-drēnˌ] is a sympathomimetic drug of the phenethylamine and amphetamine chemical classes used as a nasal/sinus decongestant and stimulant or wakefulness-promoting agent. The salts pseudoephedrine hydrochloride and pseudoephedrine sulfate are found in many over-the- or phenylephrine Phenylephrine or Neo-Synephrine is an α1-adrenergic receptor agonist used primarily as a decongestant, as an agent to dilate the pupil, and to increase blood pressure. Phenylephrine has recently been marketed as a substitute for pseudoephedrine (e.g., Pfizer's Sudafed ), but there are recent claims that oral phenylephrine may be no more effective. Decongestant nasal sprays and eye drops often contain oxymetazoline Oxymetazoline is available over-the-counter as a topical decongestant in the form of oxymetazoline hydrochloride in nasal sprays such as Afrin, Dristan, Vicks Sinex, and Mucinex Full Force. It was developed from Xylometazoline at E.Merck Darmstadt by Fruhstorfer in 1961 and are used for topical decongestion. Pseudoephedrine acts indirectly on the adrenergic receptor system while phenylephrine and oxymetazoline are direct agonists. The effects are not limited to the nose and these medicines may cause hypertension Hypertension is a chronic medical condition in which the blood pressure is elevated. It is also referred to as high blood pressure or shortened to HT, HTN or HPN. The word "hypertension", by itself, normally refers to systemic, arterial hypertension (high blood pressure) through vasoconstriction Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, particularly the large arteries, small arterioles and veins. The process is the opposite of vasodilation, the widening of blood vessels. The process is particularly important in staunching hemorrhage and acute blood loss. When, but most decongestants are not pronounced stimulants due to lack of response from the other adrenoreceptors. Besides hypertension, common side effects include sleeplessness, anxiety, dizziness, excitability, and nervousness.
Decongestants are normally paired with antihistamines A histamine antagonist is an agent that serves to inhibit the release or action of histamine. Antihistamine can be used to describe any histamine antagonist, but it is usually reserved for the classical antihistamines that act upon the H1 histamine receptor to lessen this effect, but the combination of both classes of drugs do not necessarily cancel the side effects of each other.[citation needed]
Topical nasal or ophthalmic decongestants quickly develop tachyphylaxis Tachyphylaxis is a medical term describing 'A rapid decrease in the response to a drug after repeated doses over a short period of time'. Increasing the dose of the drug will not increase the pharmacological response. Tachyphylaxis may develop with an initial dose. The cause of this phenomenon is depletion of the neurotransmitter that is involved (a rapid decrease in the response to a drug after repeated doses over a short period of time). Long-term use is not recommended since these agents lose effectiveness after a few days.
List of Decongestants
Common decongestants include:
- Ephedrine Ephedrine is a sympathomimetic amine commonly used as a stimulant, appetite suppressant, concentration aid, decongestant, and to treat hypotension associated with anaesthesia
- Levo-methamphetamine
- Naphazoline Naphazoline is the common name for 2-(1-naphthylmethyl)-2-imidazoline hydrochloride. It is a sympathomimetic agent with marked alpha adrenergic activity. It is a vasoconstrictor with a rapid action in reducing swelling when applied to mucous membrane. It acts on alpha-receptors in the arterioles of the conjunctiva to produce constriction,
- Oxymetazoline Oxymetazoline is available over-the-counter as a topical decongestant in the form of oxymetazoline hydrochloride in nasal sprays such as Afrin, Dristan, Vicks Sinex, and Mucinex Full Force. It was developed from Xylometazoline at E.Merck Darmstadt by Fruhstorfer in 1961
- Phenylephrine Phenylephrine or Neo-Synephrine is an α1-adrenergic receptor agonist used primarily as a decongestant, as an agent to dilate the pupil, and to increase blood pressure. Phenylephrine has recently been marketed as a substitute for pseudoephedrine (e.g., Pfizer's Sudafed ), but there are recent claims that oral phenylephrine may be no more effective
- Phenylpropanolamine Phenylpropanolamine , also known as norephedrine and oxyamphetamine, is a psychoactive drug of the phenethylamine and amphetamine chemical classes which is used as a stimulant, decongestant, and anorectic agent. It is commonly used in prescription and over-the-counter cough and cold preparations. In veterinary medicine, it is used to control
- Propylhexedrine Propylhexedrine is a stimulant drug related to methamphetamine. It is used mainly to provide temporary symptomatic relief of nasal congestion due to colds, allergies and allergic rhinitis. Being a vasoconstrictor used to decongest nasal mucosa, it is administered by inhalation. Propylhexedrine is most commonly found in over the counter Benzedrex
- Pseudoephedrine Pseudoephedrine [pronunciation: so͞oˌdō-ĭ-fĕdˈrĭn or so͞oˌdō-ĕfˈĭ-drēnˌ] is a sympathomimetic drug of the phenethylamine and amphetamine chemical classes used as a nasal/sinus decongestant and stimulant or wakefulness-promoting agent. The salts pseudoephedrine hydrochloride and pseudoephedrine sulfate are found in many over-the-
- Synephrine Synephrine is a drug commonly used for weight loss. While its effectiveness is widely debated, synephrine has gained significant popularity as an alternative to ephedrine, a related substance which has been made illegal or restricted in many countries due to its use as a precursor in the illicit manufacture of methamphetamine. Products containing
- Tetrahydrozoline Tetrahydrozoline is a derivative of imidazoline, which is found in over-the-counter eye drops and nasal sprays. Other derivatives include naphazoline, oxymetazoline, and xylometazoline. Poisoning can result from an overdose
Uncommon and/or discontinued decongestants include:
- Cyclopentamine Cyclopentamine is a sympathomimetic alkylamine, classified as a vasoconstrictor. Cyclopentamine was indicated in the past as an over-the-counter (OTC) medication for use as a nasal decongestant, notably in Europe and Australia, but has now been largely discontinued possibly due to the availability, effectiveness, and safety of a structurally
- Epinephrine Epinephrine is a hormone and neurotransmitter. When produced in the body it increases heart rate, contracts blood vessels and dilates air passages and participates in the "fight or flight" response of the sympathetic nervous system. It is a catecholamine, a sympathomimetic monoamine produced only by the adrenal glands from the amino
- Fenoxazoline histamine antagonists
- Levonordefrin Levonordefrin , also known as α-Methylnorepinephrine (α-Me-NE), is a psychoactive drug used as a topical nasal decongestant and vasoconstrictor in dentistry. It is also a metabolite of the antihypertensive drug methyldopa, and plays a crucial role in its pharmacology and therapeutic benefits
- Mephentermine Categories: Amphetamines | Alpha-adrenergic agonists | Cardiac stimulants | Decongestants | Stimulants
- Metizoline histamine antagonists
- Norepinephrine Noradrenaline (abbreviated NA or NAd) or norepinephrine (INN) (abbreviated norepi or NE) is a catecholamine with dual roles as a hormone and a neurotransmitter
- Tramazoline histamine antagonists
- Tuaminoheptane histamine antagonists
- Tymazoline histamine antagonists
See also
- Adrenoreceptor
- Expectorants
- Nasal congestion Nasal congestion is the blockage of the nasal passages usually due to membranes lining the nose becoming swollen from inflamed blood vessels. It is also known as nasal blockage, nasal obstruction, blocked nose, runny nose, stuffy nose, or stuffed up nose
- Topical decongestant Topical decongestants are decongestants applied directly to the nasal cavity. By applying them directly to the site of action, topical decongestants relieve nasal congestion while reducing the side effects associated with systemically-acting decongestants, such as high blood pressure. Topical decongestants should only be used by patients for a
References
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Categories: Decongestants
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