What antihistamine is best for me

Q: Every summer, my nose runs, and my eyes itch from my allergies. Claritin® has worked for me in the past, but this year is different. I tried Allegra®, but it’s not helping, either. What other antihistamine could I try?
Antihistamines work by keeping histamine locked away inside your body. Histamine is a compound that triggers inflammation. Histamine is stored in specialized cells in your body called mast cells. When you encounter something you’re allergic to, these storage cells open up, releasing the stored histamine into your bloodstream. The freed histamine triggers the symptoms we associate with an allergic reaction: stuffy or runny nose, itchy eyes, and sinus pressure.
Antihistamines work by keeping histamine tucked away safely inside your mast cells. This is why antihistamines work best if you take them at least 1 hour BEFORE being exposed to whatever sets off your allergies.
Which antihistamine should you choose? That depends on which one works best for you and how much drowsiness it can cause.
There are 2 main categories of antihistamine medicines to choose from: sedating ones and non-sedating ones. The sedating antihistamines are older drugs that often cause drowsiness. They also can help dry up a runny nose and watery eyes. Newer antihistamines cause less drowsiness but are less helpful at drying up a runny nose.
Some antihistamines relieve allergy symptoms better with some people than with others. Many people have to try more than one before they find the one that works best for their allergy symptoms while causing the least drowsiness.
How important to you is avoiding drowsiness? Older antihistamines cause at least some drowsiness in most people. If this is a concern for you, start with the newer antihistamines because they cost little to no drowsiness.
One of the best antihistamines is loratadine, also known as Claritin® or Alavert®. It’s taken only once a day and rarely causes drowsiness. If loratadine doesn’t relieve your symptoms, you could try the non-sedating antihistamine Allegra® or fexofenadine, available in either twice a day or once a day versions.
If those don’t work for you, try cetirizine (Zyrtec®) or Xyzal®. Cetirizine is transformed in your body to levocetirizine, which is Xyzal®, making them basically the same medicine. They are taken once daily, and they can cause drowsiness but only in about 10% of people.
If Claritin®, Allegra®, Zyrtec® or Zyzal® aren’t giving you enough relief, try one of the older sedating antihistamines. The most powerful is Benadryl®, also known as diphenhydramine. It helps with more severe allergic symptoms but will cause drowsiness in most people. You can buy double-strength diphenhydramine as a sleeping pill without a prescription as Tylenol PM® or Sominex II. Benadryl® should be taken 3 to 4 times a day for best results. Some people take it just at night and use a less sedating antihistamine for allergy relief during the day.
There are several older antihistamines still available, including chlorpheniramine, brompheniramine, and triprolidine. Triprolidine causes less drowsiness than the other older antihistamines and seems to have more drying action as well. Surgeons used to take it to keep from having their nose drip while performing procedures. It’s only available as Actifed®, which contains both triprolidine and the original version of Sudafed®. I prefer using it over the others because it relieves my runny nose, watery eyes, and my stuffy nose at the same time.
5 Tips on Choosing an Antihistamine:
1. Don’t Wait.
Antihistamines work best if they are taken BEFORE you come in contact with what you are allergic to. Don’t wait until your nose stuffs up, and your eyes start itching.
2. Choose not to snooze.
Select non-sedating antihistamines like loratadine (Claritin®) or fexofenadine (Allegra®), or minimally sedating ones like cetirizine (Zyrtec®) or Zyzal®, especially if you have to drive or use machinery.
3. Don’t give up.
If your first antihistamine choice doesn’t help you, try another one. It’s not unusual to get very little relief from one antihistamine, then good results with a different one.
4. Consider a combo.
For additional relief, add a nasal spray or decongestant to your antihistamine. Flonase® nasal spray or my own favorite, triprolidine/pseudoephedrine (Actifed®) tablets are excellent choices for runny and stuffy nose symptoms.
5. Avoid Sudafed PE® and generic phenylephrine.
If you have high blood pressure, avoid taking decongestants. If you need relief from nasal congestion, I strongly recommend the original versions of Sudafed® over the ones currently available in the cough and cold medicine section. Bring photo identification to purchase it from the pharmacy.  

Dr. Louise Achey, Doctor of Pharmacy, is a 40-year veteran of pharmacology and author of Why Dogs Can’t Eat Chocolate: How Medicines Work and How YOU Can Take Them Safely. Check out her NEW website TheMedicationInsider.com for daily tips on how to take your medicine safely. ® 2020 Louise Achey