Nasal decongestants mainly act as agonists on alpha adrenergic receptors. Drugs like oxymetazoline, xylometazoline and phenylephrine belongs to this category. Few of the drugs like pseuodephedrine can also act as nasal decongestant.
Nasal decongestants what are them hazard decongestants these nasal decongestants contain the drugs such as alpha one agonies and they produce nasal vasoconstriction locally so they relieve the congestion so our phone a goon is mainly act as the nasal decongestants so this is one of the drug which is an alpha one oconus and this is phenol a frame you can compare
This finale frame with the what of the katha calamine epinephrine so even if he is having this type of structure what is the difference between these two if you observe phenylephrine is having no oh h group at the third portion so phenylephrine is not a catechol mi and it lacks the voyage group at the third portion so because of this lack of voyage group now
Phenylephrine is selective for the alpha 1 receptors actually a prefering is selective for both alpha as well as beta is aptos but finn anything because of lack of voyage group at the third question it is said to further alpha 1 receptors so phenylephrine is a select 2 alpha 1 agonist similar other alpha 1 agonies include this is the one of the tribe xylem at
Azzolini this rug is having the imagery nucleus this emitted role in nucleus is attached to the final ring which is again attached with the two methyl groups so this finally gives the xylene ring this is a drug having xylem ring system which is attached to the image or in metal side shine so this is the xylo meta zoli and then the drug here is the oxymetazoline
And you can observe the only difference is oxymetazoline xanga which group adds into the methyl group on the bedsheet so these are the two brags zeno matazo lean and oxymetazoline which are the image rolling derivatives similarly and the drug is the nafa jolene you can observe that in the navajo lean naphthyl ring system is present which is again attached to the
Emitter jolene ring system one of the advantage of this novel jolene is that this can be used both for nasal as well as ocular congestion so it is not only a nasal decongestant it is also an ocular decongestant what are other nasal decongestants so this is a monofin mix it acting track which is having the voyage group with our configuration and methyl group with
S configuration so this is the drug if it drain which is hang one or two s configuration similarly its isomer is the pseudo f it drain which is hanging the s configuration at the o hitch and our conversation at the ch t so shrewder if it really has oneness to our configuration if we train previously used as a nasal decongestant and bronchodilator but nowadays it
Is not preferred as a nasal decongestant because of its adverse effects on the cardiovascular system as well as its effect on the drug addiction so pseudo if it ring is only one of the drug used as a nasal decongestant how they act so these nasal decongestants mainly act on the alpha 1 receptor so let us see how these tags are mainly acting so suppose this is a
Nasal mask class smooth muscle notice nasal vascular smooth muscle is equipped with the alpha 1 receptors and whenever nasal decongestants act as a gonna stir on this alpha 1 receptors these receptors are activated so that they will convert the fast water in – tall to the fast water to – talk activated system now this phosphatidyl ida star which is activated then
Releases the ip3 and diacylglycerol i know start triphosphate and diacylglycerol now these two minute us are espousal for the increase in the within the vast glass smooth muscle now the razor calcium within the vascular smooth muscle leads to the contraction of the last class smooth muscle in this way nasal decongestants produce vasoconstriction at the nasal blood
Vessels but how this can produce the reef of congestion so suppose this is the normal blood vessel under normal conditions but when it is under when the vasodilatation because of the congestion the nasal blood results are going to be dilated now when these are dilated the nasal pathway is going to be congested so that results in the stuffy nose and difficulty
In breathing in such situation nasal decongestants can cause vasoconstriction of the nasal blood vessels thereby they increased and nasal pathway leading to the relief of the condition seen this way nasal decongestants acts as a local vasoconstrictors within the nasal blood vessels so this vasoconstriction of the nasal that results cause a relief of the nasal
Block what are the side effects of these drugs because these let’s act locally they also produce local side effects so the first one is the nasal irritation sneezing burning and nasal sinus as these drugs are going to decrease the nasal secretions so in hazzard dryness is also observed with these strikes so all these are the local effects which can be easily
Tolerated apart from these side effects one of the limitation of the nasal decongestants is the rebound condition so the rebound condition is a one of a reverse effect of the nasal decongestants when they are used continuously for more than three days so in such situation they increase the condition by increasing the swelling redness as well as the nasal block
So the exact mechanism for this is not clear but any contracting mechanisms may be developer within these three days which may further increase the condition how these dads are given so these drugs are given as nasal sprays so fear of the lights which are given as an acid sprays include the drugs like oxymetazoline xylo meta saline and pseudoephedrine similarly
These lips can also be given as the syrups as well as tablets so throughout the night which are given as syrups and tablets include phenylephrine and pseudo fa dream you can observe that sooner if a drink can be given as a nasal spray syrups as well as tablets that’s about the nasal decongestants nasal decongestants or the drugs which produce a quick and prompt
Relief of the nasal condition and have an important role in the nasal block and stuffy nose but only one of the limitation of these drugs is that this drug should be used one for less than three days and when they are used for more than three days they can further increase the nasal congestion
Transcribed from video
Nasal decongestant – How they act? By egpat