What Are Common Antihistamines?

Man using a tissue to help his son blow his nose
Common antihistamines include brompheniramine (Children’s Dimetapp Cold), clemastine (Dayhist, Dayhist Allergy), dimenhydrinate (Dramamine), diphenhydramine (Benadryl, Nytol, Sominex), doxylamine (Vicks NyQuil, Tylenol Cold and Cough Nighttime), Cetirizine (Zyrtec), desloratadine (Clarinex), fexofenadine (Allegra), ketotifen (Alaway, Zaditor), levocetirizine (Xyzal), loratadine (Alavert, Claritin), and others.

Antihistamines are drugs used to treat symptoms of allergies. The body produces a chemical in the body called histamine when it is exposed to allergies. Histamines are released to attack allergens but they cause symptoms associated with allergies such as itching, runny nose, sneezing, hives, and itchy and watery eyes. 

Antihistamines may also be used to treat other conditions such as: 

Depending on the specific medicine and its use, antihistamines are available as pills, liquids, gels, nasal sprays, and eye drops. Many are available over-the-counter (OTC) and some require a doctor’s prescription. 

Allergy Drugs List

There are two types of antihistamines: 

  • First-generation antihistamines
    • The first type of antihistamines developed
    • Cheaper and widely available
    • They work in the part of the brain that controls nausea and vomiting and so they are also used to prevent motion sickness 
    • First-generation antihistamines commonly cause drowsiness and are sometimes used to treat insomnia 
    • Examples of common first-generation antihistamines include:
      • Brompheniramine (Children’s Dimetapp Cold
      • Carbinoxamine (RyVent, Karbinal ER)
      • Chlorpheniramine (Chlor-Trimeton, Actifed Cold)
      • Clemastine (Dayhist, Dayhist Allergy)
      • Dexchlorpheniramine 
      • Dimenhydrinate (Dramamine)
      • Diphenhydramine (Benadryl, Nytol, Sominex)
      • Doxylamine (Vicks NyQuil, Tylenol Cold and Cough Nighttime)
      • Hydroxyzine (Vistaril)
      • Meclizine (Bonine, Medi-Meclizine, Travel-Ease)
      • Promethazine (Phenadoz, Promethegan, Phenergan)
      • Triprolidine
  • Second-generation antihistamines
    • These are newer types of antihistamines
    • They can treat allergy symptoms without causing drowsiness
    • Examples of common second-generation antihistamines include:
      • Alcaftadine (Lastacaft)
      • Azelastine (Optivar)
      • Bepotastine (Bepreve)
      • Bilastine (Ilaxten)
      • Cetirizine (Zyrtec)
      • Desloratadine (Clarinex)
      • Emedastine (Emadine)
      • Epinastine (Elestat)
      • Fexofenadine (Allegra)
      • Ketotifen (Alaway, Zaditor)
      • Levocetirizine (Xyzal)
      • Loratadine (Alavert, Claritin)
      • Olopatadine (Pazeo, Patanol, Pataday)
      • Rupatadine (Rupafin)

What Are Side Effects of Antihistamines?

Common side effects of antihistamines include: 

  • Drowsiness (more pronounced in first-generation antihistamines)
  • Dry nose
  • Dry mouth
  • Headache
  • Dizziness
  • Nausea 
  • Vomiting
  • Confusion
  • Irritability
  • Blurred vision
References
Image Source: iStock Images

https://familydoctor.org/antihistamines-understanding-your-otc-options/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3650962/

https://www.aocd.org/page/Antihistamines