They are often used if other agents are ineffective or intolerable.
Autoinjectable epinephrine: This is used to treat a life-threatening allergic reaction known as anaphylaxis, which may be caused by severe allergic response to foods, drugs, or insect stings.
Decongestants: These relieve a stuffy nose by constricting blood vessels, which limits the amount of secretions coming from the inner lining of the nose.
They are available as nasal sprays, pills, and liquids.
Allergies occur when the body's immune system responds to a substance it considers an "invader." Substances that provoke the immune system into an allergic response are known as allergens. What might trigger a life-threatening allergic response in one person might cause absolutely no harm in another.
The physiological mechanism of allergic reactions is the same, however, in everyone.
Nasal corticosteroids can cause nasal dryness or irritation, nosebleed, throat irritation, headache, nausea, vomiting, cough, and fungal infections of the throat with long-term use.
Topical corticosteroids for skin allergies can cause burning, itching, redness, and changes to skin color and thinning of skin.
Newer antihistamines are said to be non-sedating, although some users may experience drowsiness even from these.
All antihistamines work in the same way: by competing with histamine to prevent or reduce the characteristic signs and symptoms of an allergic reaction: swelling, tearing, itching, and increase in bronchial and other secretions.
Topical immunomodulators for skin allergies may cause stinging, burning, irritation, and itching at the application site. Other drugs that cause drowsiness, such as sleeping medications, narcotic pain medications, sedatives, muscle relaxants, antidepressants and seizure medications.
Drugs with anticholinergic activity such as amitryptiline and other tricyclic antidepressants, antipsychotics like chlorpromazine, certain drugs to prevent vomiting (prochlorperazine and promethazine.
Nasal anticholinergics: A runny nose is a common complaint among those with allergic rhinitis.