Itchy eyes, sneezing, congestion and a runny nose are all signs of allergies. Whether your allergies are from pollen, pet dander or dust, there are several drugs that treat the symptoms. They are available over the counter or by prescription and are given in the form of pills, nasal sprays, shots or through an inhaler. The side effects of each medication vary depending on how it is taken.
Decongestants
Decongestants help to reduce swelling in the nasal passages. Common decongestants used in allergy medication are pseudoephedrine and phenylephrine. According to www.drugs.com, the most common side effects of pseudoephedrine include mild loss of appetite, feeling excited or restless, sleep problems and itching. Examples of decongestant medications that use the drug pseudoephedrine are Sudafed, Chlor Trimeton Nasal Decongestant and Suphedrin. Phenylephrine can cause headaches, nausea, dizziness, restlessness and stomach irritation, according to www.drugs.com. Examples of decongestant medications that use phenylephrine are Sudafed PE, Sudogest PE and Phenyl-T.
Antihistamines
Antihistamines act by blocking histamine, which is triggered during an allergic reaction. Histamine causes swelling, itching and an increase in mucous production. Loratadine and diphenhydramine are two examples of antihistamines. According to www.drugs.com, loratadine has no common side effects. Loratadine is sold as Claritin, Clear-Atadine and Dimetapp Children's ND. Diphenhydramine is found in Benadryl, Diphedryl and Dytan.
Combination Decongestants and Antihistamines
Many allergy medications use both decongestants and antihistamines. Examples are Claritin-D and Zyrtec-D.
Leukotriene Modifiers
Leukotrienes are produced in the body in response to an allergen. Leukotriene modifiers block these chemicals. Montelukast is a leukotriene modifier sold as Singulair.
Steroids
Steroids reduce inflammation that is caused by allergens. Steroids have several side effects including weight gain, high blood pressure, high blood sugar and fluid retention. Prednisone is used orally to treat allergies. Steroids given nasally and in the eye have less systemic effects on the body compared with other routes. Flonase, Rhinocort and Nasocort are commonly used nasal steroids. Ophthalmalic eye drops include Inflamase Forte, Lotemax and Dexasol. All steroids are available only by prescription.
