Cough and Allergy Medications During Lactation: What You Need to Know About Infant Sedation Risks
When you're breastfeeding and hit with a bad cold or allergies, the last thing you want is to choose between feeling better and keeping your baby safe. But some common cough and allergy meds can make your baby dangerously sleepy - even from a single dose. The truth is, not all medications are created equal when it comes to breast milk. Some pass through in tiny, harmless amounts. Others? They can turn a lively newborn into a lethargic, hard-to-wake infant. And in rare but devastating cases, the results have been fatal.
Why Some Meds Are Riskier Than Others
It’s not about the drug itself - it’s about how your body turns it into something else, and how your baby’s tiny system handles it. Codeine, once a go-to for postpartum pain and cough, is now one of the most dangerous choices for nursing moms. It’s metabolized into morphine in your liver. But here’s the catch: about 1 in 100 people, especially those of Caucasian descent, are "ultra-rapid metabolizers." That means their bodies turn codeine into morphine way too fast. That morphine then shows up in breast milk - and your baby, especially if they’re under two months old, can’t process it. Their liver isn’t mature enough. The result? Deep sedation, slow breathing, even death. The FDA issued a black box warning in 2017. The Breastfeeding Network says outright: don’t use codeine while breastfeeding. There are documented cases of infants dying after their mothers took just one pill.First-Generation Antihistamines: The Silent Sleepers
Diphenhydramine - better known as Benadryl - is everywhere. It’s in nighttime cold meds, allergy pills, and even sleep aids. But it’s also one of the top reasons moms call the InfantRisk Center. Studies show that about 1.6% of infants exposed to diphenhydramine through breast milk become noticeably sleepy. That doesn’t sound like much - until you see it. One mom on Reddit shared how her 6-week-old wouldn’t wake up to feed after she took one Benadryl. The ER confirmed it was likely the medication. The Royal Women’s Hospital in Australia warns: "Sedating antihistamines are not recommended because the medicine may pass into your breast milk and make your baby drowsy." These drugs don’t just cause drowsiness. They can reduce feeding frequency, lower milk intake, and even affect your baby’s breathing pattern. And it’s not just Benadryl. Chlorpheniramine and hydroxyzine carry the same risks. They’re in the L2-L3 category - meaning they’re "possibly safe," but the trade-off isn’t worth it when better options exist.The Safer Alternatives: Second-Generation Antihistamines
The good news? You don’t have to suffer. Second-generation antihistamines like cetirizine (Zyrtec), loratadine (Claritin), and fexofenadine (Allegra) are the clear winners for breastfeeding moms. They’re classified as L1 - the safest category. They transfer minimally into breast milk - sometimes less than 0.1% of your dose. Multiple studies and expert groups, including the American Academy of Pediatrics and Cleveland Clinic, agree: these are the preferred choices. One mom on BabyCenter wrote: "I’ve taken Zyrtec daily for three months with my 3-month-old. No changes in his sleep, feeding, or mood." That’s not an outlier. Surveys show that 68% of mothers who used codeine noticed changes in their baby’s alertness. Only 12% using ibuprofen did. And when it comes to antihistamines, loratadine has a 4.3/5 safety rating from breastfeeding mothers on Drugs.com. Diphenhydramine? 2.1/5.What About Cough Suppressants?
Dextromethorphan - the main ingredient in Robitussin, Delsym, and many OTC cough syrups - is one of the safest options. It transfers into breast milk at only 0.1% of the maternal dose. That’s barely measurable. The InfantRisk Center lists it as L1. No documented cases of infant sedation. No warnings. Just a quiet, effective way to calm a nagging cough without putting your baby at risk.
Decongestants: The Hidden Milk Supply Killer
Pseudoephedrine (Sudafed) is often recommended for nasal congestion. But here’s the catch: it doesn’t sedate babies. It kills your milk supply. A 2003 study found that just one dose of pseudoephedrine reduced milk production by 24% within 24 hours. That’s huge. And it’s not just a temporary dip - it can last days. WebMD and the Academy of Breastfeeding Medicine both advise avoiding it unless absolutely necessary. Even then, use the lowest dose for the shortest time. If you’re struggling with congestion, try saline sprays or a neti pot instead. They work. And they don’t touch your supply.Nasal Steroids: The Underused Hero
If your main issue is allergies causing a runny nose or sinus pressure, nasal sprays like fluticasone (Flonase) or budesonide (Rhinocort) are ideal. They’re designed to act locally - in your nose - with almost no absorption into your bloodstream. Less than 0.1% of the dose enters your system. That means almost nothing reaches your milk. The American Academy of Family Physicians recommends them as first-line treatment for allergic rhinitis during breastfeeding. No sedation risk. No milk supply impact. Just relief.Timing Matters - Even With Safe Meds
Even if you pick the safest option, timing your dose can make a difference. Experts recommend taking your medication right after you breastfeed. That gives your body time to clear most of it before the next feeding. For drugs like cetirizine or loratadine, which have a half-life of about 8-10 hours, waiting 3-4 hours before nursing reduces exposure even further. If you’re forced to use a sedating medication - say, a one-time dose of Benadryl for a severe reaction - wait at least 3-4 hours before the next feed. And never, ever use it routinely.
What to Watch For in Your Baby
If you’ve taken any new medication, watch your baby closely for:- Excessive sleepiness - harder than usual to wake for feeds
- Reduced feeding frequency - fewer wet diapers, less weight gain
- Shallow or irregular breathing
- Lethargy or unresponsiveness
What About Pumping and Dumping?
Most of the time, pumping and dumping isn’t necessary. It won’t speed up clearance of the drug from your system - your body does that on its own. And it can hurt your milk supply. The only exceptions are high-risk medications like codeine, where the risk to the baby is severe and immediate. Even then, experts say pumping and dumping should be a last resort. Focus on timing and choosing safer meds instead.What’s Changed Since 2020?
The landscape has shifted dramatically. In 2018, only 9 cough and allergy meds had sedation warnings in the LactMed database. Today, there are 17. Codeine was removed from recommended pain relievers for nursing mothers by the Academy of Breastfeeding Medicine in 2021. OTC products now have more non-drowsy options - 68% of allergy meds on shelves are labeled "non-drowsy," up from 42% in 2015. New tools like the LactaMap app now give real-time, personalized risk assessments based on your baby’s age and your medication. And pharmacogenetic testing is emerging - a simple cheek swab can now tell you if you’re an ultra-rapid metabolizer of codeine before you ever take it.Bottom Line: What to Take - and What to Avoid
Safe to use: Cetirizine (Zyrtec), loratadine (Claritin), fexofenadine (Allegra), dextromethorphan (Robitussin), ibuprofen, fluticasone (Flonase), budesonide (Rhinocort), saline sprays. Avoid: Codeine, diphenhydramine (Benadryl), chlorpheniramine, hydroxyzine, pseudoephedrine (Sudafed). If you’re unsure, call the InfantRisk Center at 1-806-352-2519. They’re available 24/7 and staffed by pharmacists who specialize in breastfeeding safety. Don’t guess. Don’t rely on internet forums. Your baby’s safety isn’t worth the risk.Is it safe to take Benadryl while breastfeeding?
Benadryl (diphenhydramine) is not recommended while breastfeeding. It can pass into breast milk and cause excessive drowsiness in infants, especially newborns. While not every baby reacts, the risk is real - and documented. Even a single dose has led to babies being too sleepy to feed properly. Safer alternatives like Zyrtec or Claritin are available and just as effective for allergies.
Can I take codeine if I’m breastfeeding?
No. Codeine is contraindicated during breastfeeding. It’s metabolized into morphine, and some mothers convert it too quickly, leading to dangerously high levels in breast milk. Infants, especially those under two months, can develop life-threatening respiratory depression from even a single dose. The FDA, the American Academy of Pediatrics, and the Breastfeeding Network all warn against its use. Ibuprofen or acetaminophen are safer choices for pain or cough.
Which allergy medicine is safest while breastfeeding?
Cetirizine (Zyrtec) and loratadine (Claritin) are the safest oral antihistamines for breastfeeding mothers. They transfer minimally into breast milk, have no documented cases of infant sedation, and are rated L1 - the safest category. Fexofenadine (Allegra) is also safe. These are preferred over older antihistamines like Benadryl, which carry sedation risks.
Does pseudoephedrine (Sudafed) affect breast milk supply?
Yes. Pseudoephedrine can reduce milk production by up to 24% within 24 hours of taking it. It doesn’t sedate the baby, but it can make breastfeeding much harder by lowering your supply. If you need a decongestant, try a saline nasal spray or a neti pot instead. If you must use Sudafed, take the lowest dose for the shortest time possible and monitor your supply closely.
Should I pump and dump after taking medication?
Pumping and dumping is rarely necessary. Your body clears medications naturally over time. Pumping won’t speed this up - and it can hurt your milk supply by signaling your body to produce less. The only exceptions are high-risk drugs like codeine, where the risk to the baby is severe. For most medications, timing your dose after a feeding is more effective than pumping.
How do I know if my baby is reacting to my medication?
Watch for signs like unusual sleepiness, difficulty waking for feeds, reduced feeding frequency, fewer wet diapers, or shallow breathing. If your baby seems unusually lethargic or unresponsive after you take a new medication, stop it immediately and contact your pediatrician. These symptoms can appear within hours and require prompt attention.
About Author
It’s astonishing how many mothers are still misled by outdated advice. The science is clear: codeine is a ticking time bomb in lactation. I’ve seen families shattered by this ignorance. The FDA warning isn’t a suggestion-it’s a lifeline. We need better education, not just pamphlets, but mandatory counseling in OB offices. This isn’t about caution. It’s about survival.
One must interrogate the epistemological foundations of these so-called "safety ratings." The L1 classification, while statistically reassuring, is predicated on population-level pharmacokinetics that utterly neglect individual variability in neonatal hepatic maturation-particularly in preterm or low-birth-weight infants. The reductionist framing of "safe" versus "unsafe" is a dangerous fallacy, a pharmacological catechism that absolves clinicians of nuanced risk-benefit calculus. Moreover, the reliance on LactMed as an authoritative corpus ignores its proprietary biases and funding dependencies. The real issue isn’t the drug-it’s the institutionalized reductionism of maternal-infant pharmacology.
This is such an important topic. As a dad from Nigeria, I’ve seen moms struggle with this-some afraid to take anything, others taking whatever’s on the shelf. I’m glad someone laid it out so clearly. The part about pseudoephedrine killing milk supply? That’s something no one talks about. My sister-in-law nearly gave up breastfeeding because she didn’t know. Sharing this post saved her. Thank you.
Thank you for this incredibly thorough and accurate guide. As a board-certified lactation consultant, I wish every OB and pediatrician would distribute this exact resource. The distinction between first- and second-generation antihistamines is critical-and so often misunderstood. I always recommend Zyrtec or Claritin as first-line, and I’ve never seen a single case of sedation in infants when mothers follow the timing advice. Also, please note: saline sprays and neti pots are not "alternatives"-they’re foundational. So many moms overlook them because they seem "too simple."
For anyone reading this: if you’re unsure, call InfantRisk. They’re free, they’re experts, and they don’t sell anything. No guesswork. Ever.
I was so scared after my first baby got super sleepy after I took Benadryl for a rash. I thought I was a bad mom for taking it-until I found this. Now I keep Zyrtec in my purse at all times. It’s a game-changer. You don’t have to suffer. You don’t have to feel guilty. There’s a safe way. And you’re not alone.