Certain Allergy Medications Can Seriously Impact Your Ability to Drive or Operate Machinery

some antihistamines, especially when taken with other medications or alcohol, can make you feel drowsy, unfocused and slow to react

Allergy Meds Could Affect Your Driving
Image: NCCC
April 2, 2019

Seasonal allergies are once again starting to take off. Before you start taking allergy medications, it's important to know that some of them, even when taken properly, can have unexpected side effects that leave you slow to react and unexpectedly drowsy. These effects can be worsened when combined with other medications or alcohol. So you need to be careful if you plan to drive or operate machinery.

Antihistamine to the rescue

When your body comes into contact with whatever triggers your allergy, it produces chemicals called histamines. Histamines cause the tissue in your nose to swell (making it feel stuffy), your nose and eyes to run, and your eyes to itch. Some people develop itchy skin rashes known as hives. Medications containing antihistamines, drugs which counteract the effect of histamines, can help relieve many different types of allergies, including hay fever and food allergies.

Antihistamine can have side effects

Anyone who takes over the counter sleep aids should be familiar with the effects of at least one antihistamine. Diphenhydramine, the antihistamine ingredient found in Benadryl, is present in many over the counter sleep aids because it can relax you and help you fall asleep. This is good news if you're having trouble sleeping, but bad news if you just want to relieve allergy symptoms before hopping in the car or operating machinery.

Information about whether an antihistamine medication can make you drowsy can be found in the product's label. In North Carolina you can be arrested for Driving While Impaired (DWI) if the effects of certain medications, including antihistamines, affect your driving ability. Rather than risk your safety and a DWI charge, read the Drug Facts label of the medication and understand the warnings before you use it.

Precautions to Take

Different antihistamines may be dosed differently. If one specific antihistamine worked for you before, take note of the dosage and make sure you get the same medication the next time.

It's also important to avoid alcohol, sedatives (sleep medications), or tranquilizers while taking some antihistamines. This information can also be found in the Drug Facts label. Alcohol and sedatives can seriously increase the sedative effects that may already occur when taking antihistamines.

Tips to Keep in Mind

  • Always follow directions for use and read warnings on the packages of the drug products you purchase.
  • Some antihistamines may cause drowsiness, and you need to exercise caution when driving a motor vehicle or operating machinery. Avoid using alcohol, sedatives, and tranquilizers while taking the product because they may increase drowsiness.
  • Know that some antihistamines take longer to work than others. Recognize that you might feel the sedating effects of these medications for some time after you've taken them and possibly even the next day.