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Woman being unwell from allergy to flower pollen.

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The past few weeks the spring allergy season has been in full force. I’m seeing adults and children coming in with severe nasal congestion and sneezing. If you have ever experienced this or even severe cold, you know how uncomfortable these symptoms can be.

Today, many allergy medications are available over-the-counter without a prescription. This can be good and bad. The good is that you don’t have to make a doctor’s appointment to get medicine for the relief of your allergy symptoms. The bad is that some of these medicines have side-effects which, if you are using them regularly, you should be aware of.

The “D” in Claritin D


All the common antihistamines are now available without a prescription: Claritin, Allegra, and Zyrtec. Each is also available as a generic: Alavert, Fexofenadine and Cetirizine. You can definitely save money with the generic, and it’s comparable to the name brand. Each of these antihistamines also comes in combination with a decongestant called pseudoephedrine. I know many patients who rely totally on Claritin-D because the decongestant component gives more relief for nasal congestion. The plain antihistamines help to sneeze and to itch more than congestion. Here’s the catch: the “D” in these decongestants can cause side effects that don’t occur with the plain antihistamine.

High Blood Pressure, Arrhythmia & Decongestants

Hypertension is a common side-effect that I see in many patients taking decongestants. When I see an otherwise healthy 20-year-old who is suffering from allergies and has been on Allegra-D for two months during the allergy season, I check their blood pressure. Often I will get a reading of something like 150/90. This tells me that the decongestant is affecting their blood pressure. If the patient stops the decongestant-antihistamine, the blood pressure usually returns to normal within 2 weeks. I often prescribe a nasal spray which can be very effective in reversing the nasal congestion and does not adversely affect blood pressure.

Decongestants can also cause palpitations or arrhythmia (erratic heartbeat) in a patient who is either very sensitive to the medication or has some cardiovascular disease that they may not be aware of. Interestingly, I have read reports where football players in good shape, who have taken decongestants for allergies, have developed arrhythmias. I believe this is because they are pushing their bodies’ strenuously and may have an enlarged heart that is super-sensitive to these medications.

Getting Some Shut-Eye

Woman feeling sick sleeping

Sleep is affected by decongestants. I have patients who think their allergies are affecting their sleep when it turns out the decongestant they are taking at night is the cause. Decongestants are similar to caffeine’s effect on the body and with a longer-lasting effect. I understand patients feel they can’t get a good night’s sleep if they have nasal congestion, but again, a combination of nasal sprays can get the same effect with fewer side-effects.

Not Good Together

Anxiety is another side-effect of decongestants that is not commonly known. I have patients that are taking anti-anxiety medications. When I find out they are also taking an over-the-counter antihistamine-decongestant, I explain to them their body is in a tug-of-war: the decongestant is revving them up and their anti-anxiety med is trying to calm them down–the mixed signals are not healthy for the body or the mind.

Gastrointestinal reflux, also commonly referred to as GERD, is worsened by decongestants. Decongestants can increase acid production in the stomach and in compensation the body regurgitates it back up the esophagus. If you are taking acid blockers for GERD, taking a decongestant is a mistake.

Allergy Drops to the Rescue

The answer to controlling severe nasal congestion due to allergies does need proper medical attention. Many of my patients can be helped by combining safer topical nasal sprays to get allergy relief. If you do have severe allergy symptoms, you should get tested to find out what you are specifically allergic to. The good news is that allergy relief has never been simpler with using sublingual allergy drops. I’ve been using the allergy drops for 15 years, and you won’t find any of my patients taking decongestants.

Enjoy the rest of your summer: Doctor’s order.

Do Allergy Drops Work?

Watch the video below to learn about Luke’s experience with allergy drops treatment to get rid of his severe allergies.

– Dr. Dean Mitchell, M.D.
Mitchell Medical Group, NYC

About the Author – Dr. Dean Mitchell, M.D.

Dr. Dean Mitchell, M.D.

Dr. Dean Mitchell, M.D. is a Board Certified Allergist and Immunologist based out of NYC. He graduated from the Sackler School of Medicine and completed training at the Robert Cooke Allergy Institute in New York City. He is also a Clinical Assistant Professor at Touro College of Osteopathic Medicine, a fellow of the American Academy of Allergy, Asthma, and Immunology, and the author of Dr. Dean Mitchell’s Allergy and Asthma Solution: The Ultimate Program for Reversing Your Symptoms One Drop at a Time. Dr. Dean Mitchell, M.D. has also been featured in The New York Times, The Huffington Post, Fitness Magazine, Dr. Oz and News NY 1. Dr. Mitchell also hosts the podcast The Smartest Doctor in the Room – a combination of a lively, personal and in-depth interview with top healthcare specialists.