The strong painkiller hydrocodone, commonly sold as Vicodin, may be safe in smaller doses for women nursing newborns, U.S. researchers say.
They found a relatively small fraction of the drug ended up in breast milk, and say that up to 30 milligrams of Vicodin per day -- for instance, 6 tablets of 5 milligrams each -- might be acceptable if weaker painkillers like acetaminophen (Tylenol) or ibuprofen (Advil) don't take care of the pain.
Hydrocodone belongs to a class of narcotic painkillers called opioids. These drugs can pass into breast milk and there have been reports linking them to life-threatening drowsiness and one death among nursing babies.
Experts currently recommend that women who have pain from tearing during delivery or Cesarean section try over-the-counter painkillers first.
If that doesn't take care of the pain, they might try opioids such as hydrocodone.
But they should stick to the prescribed dose, not take the drugs more than two to three days and see the doctor immediately if their baby is unusually sleepy or not sucking properly, said Dr. Shinya Ito of the University of Toronto, who was not involved in the new study.
For the study, Dr. Jason Sauberan of the University of California, San Diego, and colleagues measured hydrocodone and one of its by-products in breast milk from new mothers.
Their study appears in the journal Obstetrics & Gynecology.
Based on the measurements, they estimated babies would end up with a total opioid dose of less than one percent of what is given to older infants with severe pain.
But Dr. Gideon Koren, who heads The Hospital for Sick Children's Motherisk Program in Toronto, said that number could be misleading because a newborn keeps the drug in its body longer than older kids do.
"These numbers cannot replace looking at the baby, and these numbers are not reassuring," he told Reuters Health in an e-mail.