Sus

Alergia

Alergia

 

     Tulburările alergice precum febra fânului, eczemele şi astmul afectează aproximativ 25% din populaţia lumii. La subiecţii alergici, expunerea persistentă sau repetitivă la alergeni (care sunt consideraţi substanţe comune inofensive) are ca rezultat inflamaţiile cronice.

     Dar hai să o luăm cu începutul.
CE ESTE ALERGIA?

     

O reacţie alergică apare atunci când sistemul imunitar al unei persoane devine hipersensibil la anumiţi factori declanşatori (alergeni) precum anumite alimente, polen, medicamente, venin de albine sau animale.

 

      Alergenii declanşează producerea de imunoglobulină E (IgE), un anticorp pe care îl avem cu toţii în cantităţi mici şi care, în mod normal ne protejează de paraziţi şi nu de alergeni. Pe perioada expunerii la alergeni, IgE este supraprodus de organism şi astfel se eliberează histamina, cea care cauzează de fapt simptomele alergiei.

 

      Termenul de “alergie” a fost inventat de Clemens von Pirquet în anul 1906 ca o explicaţie a unor reacţii neobişnuite la anumite substanţe, pe care le aveau unii indivizi testaţi de acesta.

 

      Deşi alergiile se pot dezvolta la orice vârstă, unii cercetători susţin că acest lucru este determinat genetic. Dacă nici unul dintre părinţi nu este alergic atunci şansele de a dezvolta o alergie de către copii este de 15 %, iar procentul poate creşte până la 30%, în cazul în care doar unul dintre ei are o alergie şi la 60%,  când ambii părinţi sunt hipersensibili.

 

SIMPTOME

     O reacţie alergică poate provoca inflamaţii şi iritaţii pe piele sau în interiorul corpului însă, cu toate acestea, simptomele specifice vor depinde de tipul de alergen şi de timpul la care persoană este expusă.

 

     Iată câteva exemple de alergeni şi simptomele specifice acestora:
TIPURI DE ALERGII

 

Administrația pentru alimente și medicamente (FDA) recomandă ca persoanele cu risc de şoc anafilactic să poarte în permanență două auto-injectoare de epinefrină. Dacă o doză nu este eficientă, persoana va avea nevoie de a doua.

 

     EpiPen este doar un tip de injector recomandat. Utilizarea sa implică o doză măsurată de adrenalină cu efect în câteva minute de la apariția oricărui simptom sever. Toți injectorii au același efect, dar modalitățile de utilizare a acestora pot diferi. 

 

     Este recomandat să apeleze totuşi și serviciile de urgență.

 

TRATAMENT

Cel mai bun mod de a controla o alergie este evitarea alergenului pe cât de mult se poate, însă, acest lucru nu este intodeauna posibil.

 

Medicamentele nu vindecă alergia dar pot ajuta la ameliorarea simptomelor care devin uneori greu de suportat.

 

Înainte de administrarea oricărui produs, fie că este Rx (se eliberează pe baza unei prescripţii medicale), fie că este OTC (over the counter), este recomandat să se discute cu un medic sau farmacist.

 

  

   Sunt investigați mulți agenți farmacologici sau biologici noi care vizează diferitele etape ale căilor celulare și ale mediatorului implicate în inflamația alergică. Sunt luate în considerare, de asemenea, strategii pentru reducerea sensibilizării și promovarea toleranței la alergenii obișnuiți.

 

     Antagoniștii receptorilor de leucotriene (antileucotriene) pot de asemenea  ajuta în tratarea unor alergii pentru care alte tratamente nu au funcționat.  Acestea blochează substanţele chimice apărute în mod natural în plămâni, denumite leucotriene, care determină îngustarea şi inflamaţia căilor aeriene pulmonare, responsabile de apariţia simptomelor astmului bronşic. Un astfel de medicamente este Montelakastul.

 

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