Why Your Allergy Medicine Doesn’t Work, and What You Can Do About It

Have you noticed that your allergy medicines don’t work as well as they used to? You’re not alone. In a national survey, people with allergies reported changing their allergy medications because they’re not effective enough.

But why do allergy medications stop working? Can you really build up a tolerance to allergy medications? Here’s what you should do if you’re still sneezing and feeling stuffy after taking your allergy medicine.

What to do when allergy medication doesn’t work

If your allergy medication isn’t working, you probably want to improve your symptoms fast. The best solution depends on what’s causing your allergies to act up and what’s keeping your medication from working. 

Here’s what to do if your allergy medication isn’t working.

1. Check for changes in your immediate environment

Changes in the environment can make your allergies worse. Things like worsening air pollution, warmer temperatures, and fumes from chlorinated swimming pools make allergies act up. And some of these overlap with allergy season, so you get a double hit. This can make it seem like your allergy medication isn’t working when really it could be that it’s not strong enough to overcome your stronger symptoms. 

Check and see if there are changes in your immediate environment. Some things to consider:

• Did you recently move to a new area? You may be exposed to new levels of air pollution or different pollens and grasses.
• Did you recently get a new pet? Pet dander could be making your allergies worse. Being around a significant other’s pet or other animals could also be triggering your allergies.
• Have you been remodeling? Construction and redecorating can stir up long-settled dust and aggravate your allergies. Dust can also cling to recently moved furniture or other items that you’ve brought in from your basement, attic, or unit storage. 
• Did you garden or change your landscaping? New trees, plants, and even flowers can aggravate your allergies. If you planted something new in the fall, that pollen can worsen your allergies in the spring and summer. 

If environmental changes are worsening your allergies, you may need to adjust your medication dose or even add another medication to your plan. You may also need to come up with a plan to avoid new allergens. Allergy-tracker tools can help you plan your days so that you can avoid high pollen.

2. Get checked for new allergies

You can develop new allergies as you get older — even if you’re exposed to the same allergens year after year. 

Medications that worked for your previous allergies may not work as well for your new allergy symptoms. If your allergy medication isn’t working or you have new allergy symptoms, it may be time to visit your healthcare professional for an updated round of allergy tests. If you have new allergies, you may need to change your medications. You may also need a plan to avoid new triggers. 

3. Take your medications on schedule

A lot of people stop taking their allergy medication when their symptoms ease up or go away. But even though you aren’t sneezing and feeling stuffy anymore, those allergens are still there. Once you stop taking your allergy pills or sprays, your allergy symptoms will come back. 

If you have seasonal allergies, the best way to keep symptoms at bay is to start your allergy medication a few weeks before allergy season. That way, your immune system is ready to respond when allergens come out. 

If keeping up with daily allergy medications isn’t working for you, talk to your healthcare professional about other options like allergy shots. Allergy shots are time intensive, but they can be a great alternative to daily allergy medications.

4. Check to see if you have rebound congestion

Some medications that relieve allergy symptoms, like stuffy nose and sneezing, aren’t meant to be used long term. Medications that contain oxymetazoline and phenylephrine are only meant to be used for a short period of time. Using these medications for longer may lead to rebound congestion.

Rebound congestion develops when your body becomes used to these medications. When you try to stop using them, you develop a severe stuffy nose that can take months to go away. 

Oxymetazoline and phenylephrine are available over the counter (OTC) and are ingredients in many decongestants. But they’re not meant to be used to treat daily seasonal allergies. If you’ve been relying on these medications, you’ll need to switch to other options, like nasal steroid sprays and antihistamine pills.

5. Make sure your medications aren’t expired

Check the expiration date on your medication if you feel like it hasn’t been working. 

Taking an expired allergy medication isn’t likely to harm you. But expired medications may not work well either. The FDA advises against using expired medications. That’s because there’s no guarantee that medicines are safe and effective past their expiration date. So replace those expired medications. It may be enough to bring you relief. 

Keep in mind that epinephrine autoinjectors (EpiPens) shouldn’t be kept after their expiration date. EpiPens are used to treat life-threatening allergic reactions. 

6. Take note of your stress level

Stress can increase your sensitivity to allergens and kick your allergic response into high gear. Reflect on whether your stress levels are higher than usual. If you’ve been more stressed than usual, try to lower your stress levels using tools like meditation, therapy, or exercise. 

If you’ve stuck to your allergy-medication schedule, reduced your exposure to allergens, and tried to reduce your stress levels, and you’re still suffering from allergy symptoms, it might be time to see an allergy specialist. They’ll be able to help you assess any new allergen sensitivities and give you advice on what steps to take next.

Do people build up resistance to allergy medicines?

Developing a resistance to allergy medications isn’t common. 

Inhaled steroids, like fluticasone (Flonase) and triamcinolone (Nasacort), are first-choice treatments for chronic seasonal allergies. Both are available without a prescription and don’t lead to resistance.

Antihistamines are another popular choice for treating allergies, such as:

• Loratadine (Claritin)
• Fexofenadine (Allegra),
• Cetirizine (Zyrtec)

And studies show that people do not build up resistance to these medications.

Can you be allergic to allergy medication?

Maybe, but it’s very unlikely. There have been cases where antihistamines like cetirizine and hydroxyzine caused rashes and hives. But it’s rare for a person to be allergic to allergy medications.

If you think your allergy medication is making things worse, it's best to contact your healthcare professional for help. Get emergency medical treatment if you have symptoms of a serious allergic reaction like throat swelling or difficulty breathing.