Sneezing, itchy eyes, congestion, a runny nose and hives are just some signs of a typical allergic reaction. The Mayo Clinic says that allergies actually occur when the immune system responds to foreign invaders as pollen. Fortunately, doctors can prescribe common allergy medications for symptomatic relief.
Diphenhydramine
Diphenhydramine, commonly sold as Benadryl, works as an antihistamine medication for allergy relief. It interferes with the release of a substance called histamine from the body.
Drugs.com says that diphenhydramine's less concerning side effects include a headache, dry mouth, trouble urinating, a large prostate and fatigue. This medication can also cause dizziness and sleepiness. Phone a doctor when diphenhydramine's less serious effects remain for more than five days.
Diphenhydramine can also lead to a serious allergic reaction in people who cannot tolerate this medication. Signs of an allergic reaction include difficulty breathing, hives and swelling of the tongue, throat or lips. Call 911 as soon as these symptoms develop.
A reduced dose of diphenhydramine may be necessary when suffering with such diseases as a stomach ulcer, an enlarged prostate, bladder problems, glaucoma or high blood pressure.
As a tablet, diphenhydramine can be taken daily as needed. Drugs.com says that no more than 300mg of diphenhydramine must be taken in a 24-hour period.
Epinephrine
Epinephrine treats allergies. MedlinePlus indicates that epinephrine acts as a sympatheticomimetic agent that constricts the blood vessels and relaxes the airways.
This drug's common side effects include a headache, pale skin, sweating, vomiting, sweating and nervousness. This medication can also lead to a headache, weakness, stomach problems and shaking of the hands. Notify a doctor when epinephrine's effects remain for more than a week.
Epinephrine's serious side effects include trouble breathing and a fast or irregular heartbeat. Notify a doctor right away when epinephrine leads to these effects.
A change in epinephrine's dose may become necessary if taking such medications as doxepin, digoxin, imipramine or protriptyline.
Epinephrine is designed as a pre-filled injection that is typically injected into the thigh as needed for a severe allergic reaction.
Phenylephrine
Phenylephrine, commonly sold as Sudafed PE, Dimetapp Cold Drops, Lusonal and Nasop is another medication used to manage allergies.
Drugs.com says that phenylephrine's milder side effects include a headache, dizziness, stomach problems and trouble sleeping. This drug can also lead to restlessness. Talk to a doctor if phenylephrine's common effects last for more than a week.
Phenylephrine's serious side effects include fainting, nervousness, insomnia, tremors, shaking, unusual thoughts and behavior. This medication can also lead to tremors, shaking, decreased urination and a fast heartbeat. Call a physician when phenylephrine's serious effects develop.
A change in phenylephrine's dose may become necessary when suffering from such diseases as high blood pressure, thyroid disorder, trouble sleeping, glaucoma, anxiety, heart disease and diabetes, mental illness, heart rhythm disorders and trouble sleeping.
Phenlephrine is a tablet typically taken every four hours or as prescribed.
