Antihistamines are used in order to suppress the body's histamine response to allergens. According to the American Academy of Allergy, Asthma and Immunology (AAAAI), antihistamines are available in two generations of treatment strength. Since they prevent the activation of histamine, they eliminate allergic symptoms but do not eliminate the underlying cause of the irritation or allergic response.
Treatment Basics
Antihistamines are primarily used to treat the condition known as allergic rhinitis (hay fever), though they can also be used to treat hives and rashes according to FamilyDoctor.org. The antihistamines are most effective when ingested prior to exposure to the allergen in question, though they can also dampen down allergic reactions that are in progress.
The most common forms of antihistamines available for the treatment of allergies are pills, liquids or nasal sprays. The relief provided by all forms is temporary and ends when the medication has worn off.
Common Side Effects
The common side effects of antihistamines, according to AAAI, are drowsiness, dry mouth and constipation. Difficulty urinating is also common, especially in men who have prostate problems. When used for the treatment of children's allergies, there have been reports of antihistamines being linked to nightmares and sleeplessness.
It is important to note that these side effects are more often associated with first-generation antihistamine formulations than newer formulations. However, without advanced research on the antihistamine's history through Allergy Escape or another formulation resource, it is difficult to know if the current formulation for any given antihistamine represents first-generation or second-generation medical technology.
Over the Counter Vs. Prescription Strength
Antihistamines are available in over-the-counter or prescription strength formulations. The main differences between the two strengths lies in the speed with which symptoms are reduced, the length of the period of symptom relief and the level of side effect experienced. Prescription-strength medications generally last for longer periods of time and offer fewer symptoms of drowsiness, according to AAAI and Consumer Reports.
Long-Term Health Effects
There are some long-term health effects associated with the use of antihistamines. The primary issue is a creation of tolerance for the medication, requiring higher and higher doses to achieve the desired levels of allergy symptom relief. Lifelong users frequently switch between formulations along with increasing dosages to continue to suppress their allergic reactions.
