Benadryl is used to temporarily relieve the symptoms of allergies, hay fever, or the common cold. It’s generally safe to use. However, Benadryl can pass through breast milk and affect your child. So, it’s not the best choice if you’re breastfeeding.

Learn how Benadryl works, how using it can affect your baby, and alternatives that may be safer.

Benadryl is the brand name of an over-the-counter product that relieves minor pain, itching, and other symptoms from mild allergic reactions. Benadryl oral tablets, capsules, and liquids relieve symptoms caused by allergies, hay fever, or the common cold. Topical Benadryl cream or gel relieves itching and pain from:

  • insect bites
  • minor burns
  • sunburn
  • minor skin irritations
  • minor cuts and scrapes
  • rashes from poison ivy, poison oak, and poison sumac

The active ingredient in Benadryl sold in the United States is diphenhydramine, which is an antihistamine. It helps block histamine, a substance certain cells in your body release during an allergic reaction. Histamine causes the symptoms such as runny nose, sneezing, and itchy and watery eyes. Diphenhydramine helps reduce these symptoms.

Benadryl doesn’t affect the amount of milk your body makes. However, it may decrease the flow of milk from your breasts.

Benadryl can also be passed to your child through your breast milk when you take the pills or use it on your skin. That means Benadryl may cause side effects in children who breastfeed from mothers who take it. Newborns and infants are especially sensitive to antihistamines. The side effects of Benadryl in newborns and infants include:

  • drowsiness
  • excitability
  • irritability

If you’re breastfeeding and considering taking an antihistamine, talk with your doctor first. Your doctor will help you sort out the potential risks to your child. They may suggest taking the dose before bedtime, after you’ve finished breastfeeding for the day. Your doctor also may recommend an alternative to Benadryl.

The active ingredient in Benadryl, diphenhydramine, is a first-generation antihistamine. That means it was one of the first kinds developed. There are more side effects from these drugs than from later generations of antihistamines.

Your doctor may suggest that you use low doses of products that contain a second-generation antihistamine, like cetirizine (Zyrtec) or loratadine (Claritin), instead of Benadryl. Your doctor will likely recommend that you don’t use them too often, though. These drugs can still pass into your breast milk and make your baby sleepy, but not as much as Benadryl would.

Talk to your doctor about your best options to help relieve your allergy symptoms, especially when you’re breastfeeding. Your doctor can tell you about any over-the-counter drugs that can help relieve your symptoms safely. They can also tell you about treatments other than drugs that may help, as well as ways to help prevent symptoms in the first place.