Question

8-year-old boy suddenly developed difficulty of breathing, wheezing, skin rash, and swelling of the lips. He was accompanied by his mother during a birthday party. He is known to have peanut allergy that flares on exposure and resulted in anaphylactic shock before. In such acute setting, a lifesaving medication would work by:

Blocking both alpha- and beta-adrenergic receptors.

Stimulating both alpha- and beta-adrenergic receptors

Competing with histamine over histaminic receptors

Stimulation of muscarinic receptors in the heart

Answer 1

PEANUT ALLERGY:

• That occurs due to natural defence mechanisum which mistakenly identifies peanut as a contaminate substance
• it is a life threatening response
• symptoms: stomachache, runny nose, itchy ice, difficulty to breath and tingling in your eyes and tongue.
• anaphylaxis: severe allergic reaction that affects the entire body with in minutes or seconds after expose to the substance.

MECHANISM OF ACTION:

• TYPE 1 hypersensitivity reaction
• leads to anaphylatic reaction:- leads inflammation and allergic symptoms.
• dendritic cell mistakely recognize peanut as a foreign pathogen - recognised by T cells - release of cytokines happen(IL 4, IL 5, IL 13) - bound to receptors on undifferentiated B cells - trigger mast cells , eosinophiles and basophils results inflammation and allergy symptoms.

Blocking both alpha- and beta-adrenergic receptors

• not a right medication for peanut allergy.
• alpha and beta adrenergic receptor are G protein coupled receptors targets catecholamines (norepinephrine, epinephrine).
• it may worse the current situvation.

Stimulating both alpha- and beta-adrenergic receptors

• one of the right medication which can use for peanut allergy.
• epinephrine injection
• stimulation both alpha- and beta-adrenergic receptors will stimulate sympathetic nervous system:- which trigger by exercise and fear causing situations, cause increased physical perfomance.
• epinephrine injection:- bronchodilation, vasodialation etc.

Competing with histamine over histaminic receptors

• one of the right medication which can use for peanut allergy.
• example :- diphenhydramine
• blocking mechanism:- competitive antagonism of histamine binding to cellular receptor(H1). - H1 receptors are present in nerve endings, smooth muscles and granular cells. - blocking histamine receptor help to resolve allergic reactions.

Stimulation of muscarinic receptors in the heart.

• Stimulation of muscarinic receptors in the heart is not a firstline treatment for peanut allergy.
• muscarinic receptors are metabotropic receptors:- which directly excite postsynaptic neurones
• usually giving for cardiooprotection against ischemic injuries
• cant consider as firstline treatment for peanut allergy.

CONCLUSION:

• Strict avoidance of peanut are the best thing to avoid the peanut allergy.
• mostly its a heriditory disease
• drugs which can use as first line therapy are :-

1. Stimulating both alpha- and beta-adrenergic receptors.
2. Competing with histamine over histaminic receptors.