Discuss with your doctor the side effects of any medicine you take. With antihistamines, even those bought over the counter, follow these tips to be sure you use them safely.

  • Watch for drowsiness. Feeling sleepy and "medicated" is common with sedating antihistamines, but you may not even be aware that you are sluggish.
  • Don't drive, operate machinery, or perform other dangerous tasks if the antihistamine makes you drowsy. Some people who take antihistamines don't feel impaired by the medications. But they really are! That's why you need to follow the directions on the box or those provided by your pharmacist or doctor.
  • Don't drink alcohol while taking antihistamines. Alcohol is a depressant that can increase the sedating or drowsy effects of antihistamines. Taking certain kinds of painkillers while taking antihistamines can make you even less alert and more drowsy. Check with your doctor or pharmacist if you have a question about mixing medications.
  • Try taking sedating antihistamines at bedtime. That way, any drowsiness will cause fewer problems. Be aware, though, that even if you take it at night, the antihistamine may still cause some impairment the next day.
  • Report any side effects to your healthcare provider.
  • Don't take antihistamines without your doctor's approval if you're pregnant, trying to get pregnant, or nursing.
  • Avoid dangerous drug interactions. Make sure your doctor and pharmacist are aware of all medicines and supplements you take.