More and more formulas for allergy control are available without a prescription. Gone are the days when you could use any antihistamine you liked as long as it was Benadryl®.
With so many options, we frequently get lots of questions about over the counter allergy medication. We aren’t pharmacists, but here are a few things we do know.
Over the Counter Allergy Medication Side Effects
Any medication, whether prescribed or taken over the counter, can have possible side effects. All you have to do is watch any drug ad on TV and you will hear a list of side effects that can sound worse than the actual treatment.
Over the counter allergy medication can bring relief, but it can also bring side effects such as:
- Blurry Vision – Can be caused by older style antihistamines containing diphenhydramine (Benadryl) or newer ones with loratadine (Allegra, Claritin)
- Constipation – This is a pretty common side effect of over the counter allergy medications. Antichlogenerics (Zyrtec Allegra, Claritin) and antihistamines (Claritin, Allegra and Benadryl) can both cause this problem. Be sure to drink plenty of water when you take these medications.
- High Blood Pressure – Hypertension can be caused by oral decongestants taken to relieve nasal allergy symptoms. People taking medication for high blood pressure should talk to their doctor BEFORE taking any oral decongestant or decongenstant/antihistamine combination) If the medication name end in “-D” it probably contains a decongestant (Claritin-D, Aleve Cold & Sinus-D)
- Nose Bleeds – While rare, these can be caused by use of nasal corticosteroids and nasal anticholinergics. If you spray it in your nose, it can cause a nose bleed.
- Sleepiness – This is the original antihistamine side effect. Diphenhydramine causes sleepiness, that is why they add to so many of those “PM” formula pain relievers. Look for the “nondrowsy” formula of your favorite OTC medication.
- Upset stomach – Not a common side effect, but nasal corticosteroids can cause nausea and vomiting. Antihistamines can cause stomach problems such as nausea or constipation.
- Weight gain – In August 2010, researchers from Yale University published a study in the journal Obesity finding that people who took antihistamines regularly were heavier than people who didn’t take them at all. The study’s authors used data from the Centers for Disease Control and Prevention’s (CDC’s) National Health and Nutrition Examination Survey 2005–2006 to compare the body weight of 867 adults and their prescription antihistamine use. The two drugs most common in the study were cetirizine, now sold over-the-counter as Zyrtec, and fexofenadine, also now sold over-the-counter as Allegra
Effect of Over the Counter Allergy Medications on Drug Tests
You may not realize it until it to so late, but your over the counter allergy medication can case the tests for illegal results to return inaccurate results. Allergy medicines containing antihistamines and decongestants can cause a false positive result for amphetamine.
If your OTC allergy or cold relief contains ephedrine, pseudoephedrine, propylephedrine, phenylephrine or desoxyephedrine you may get a false positive for amphetamine. This is also true for over the counter nasal sprays such as the Vicks inhaler, or Afrin nasal spray.
Note: 9/14/2023 - "FDA held a Non-prescription Drug Advisory Committee meeting Sept. 11-12, 2023, to discuss the effectiveness of oral phenylephrine as an active ingredient in over-the-counter (OTC) cough and cold products that are indicated for the temporary relief of congestion, both as a single ingredient product and in combination with other ingredients.
The committee discussed new data on the effectiveness of oral phenylephrine and concluded that the current scientific data do not support that the recommended dosage of orally administered phenylephrine is effective as a nasal decongestant. However, neither FDA nor the committee raised concerns about safety issues with use of oral phenylephrine at the recommended dose."
If you take over the counter asthma medications such as Marax, Bronkaid tablets, Primatine Tablets you may also have a false positive for amphetamine.
If your allergies cause you to have a headache and you take Advil or Motrin you might also get a false positive for marijuana.
Before taking any drug test, be sure to disclose ALL over the counter medications you have taken in the last several weeks.
Will Over the Counter Allergy Medication Help if It Isn’t Allergy?
Lots of people wonder if they should take over the counter allergy medication for their symptoms or if they should use something else. Here are a few guidelines:
Coughs – If the source of your cough is allergic post nasal drop then an antihistamine such as loratadine or fexofenadine may help. Stay away from diphenhydramine and chlorpheniramine as they can make post nasal symptoms worse.
Eczema – Older antihistamines such as diphenhydramine may help with itching, but they will not heal the skin. Moisturizers can help soothe the skin and hydrocortisone can reduce inflammation. Those are your better options than looking to your oral antihistamine
Hives – Over the counter antihistamines may bring relief for hives. When taken on a regular basis, they can prevent hives from forming. If you suffer from chronic hives, it is best to consult with your physician to determine the cause of the hives. This is one of those times that an ounce of prevention is worth a pound of cure.
Mosquito bites – Allergy medication is only going to help if you are allergic to the proteins in the mosquito saliva. The typical mosquito bite reaction is a result of the anti-coagulant in the saliva. You can put ice on the bite to reduce swelling and itching. If you develop hives or intense itching then a topical corticosteroid or oral antihistamine may help.
If you have questions about your over the counter medications, don’t hesitate to talk to the pharmacist at the local drug store. They are a great resource and they want to help; even if you aren’t buying prescription medication.
Till next time