A neighbor may have told you that ibuprofen is bad for babies because it causes asthma. Or you may have read on the internet that cases of autism have risen sharply in recent decades due to the widespread use of acetaminophen. Or maybe you were told that you could give your baby these medications whenever needed because both are totally safe.
And then we have other common supplements for babies that offer pain relief, like gripe water and colic drops. Are these safe to use? Are there better alternatives?
The more you read, search, and talk with neighbors, the more difficult it is to make a decision. Your baby has a fever and is in pain. You wonder if it's okay to use medications and what the long-term consequences will be.
To help you make the best decision, we went through many studies that sought to find an association between acetaminophen or ibuprofen, and different conditions.
We also summarized some non-medication alternatives that you can use to make your baby feel better.
Acetaminophen and ibuprofen
Acetaminophen (aka paracetamol outside of the US, and sold as Tylenol®) is used to relieve pain and fever. Ibuprofen (sold as Advil®, Motrin®) relieves pain and fever too, but it also has anti-inflammatory properties.
Both are often used for fever, colds, toothache, sore throat, and mild-to-moderate pain. They’re also two of the most common medications used for babies and toddlers [1].
Both acetaminophen and ibuprofen have been reported to be safe to use in babies and toddlers under two years of age [2].
So, why did your neighbor tell you these were unsafe and could lead to worrying conditions like autism and asthma? Let’s first take a look at the theories behind these associations.
The theories that link acetaminophen or ibuprofen with asthma
At some point scientists began studying if acetaminophen or ibuprofen use could increase the risk of developing asthma. Let’s see what made them think this could happen in the first place.
There are three theories. None of these have been proven:
- Acetaminophen lowers glutathione. Glutathione is a potent antioxidant molecule whose levels are altered in asthma patients [3]. And, it turns out that a small clinical trial found that acetaminophen lowered glutathione levels in the blood of healthy people [4]. So the first theory is that acetaminophen may reduce the levels of glutathione in the lungs, making children more prone to develop asthma or exacerbating the disease in those who already have it.
- We stopped using aspirin. Decades ago, aspirin was the preferred medication to treat fever. Until it was linked to Reye's syndrome, a rare disorder that causes liver and brain damage [5]. Because of this, acetaminophen became the most used medication to treat fever in children. This coincided with an increase in the cases of asthma and other allergic diseases. So this theory doesn't state that acetaminophen directly causes asthma. Instead, it has been suggested that aspirin was protecting children against asthma, and that protection was lost when we stopped using it [6].
- Acetaminophen and ibuprofen increase leukotrienes. The third theory has to do with hypersensitivity to acetaminophen or ibuprofen. When we take these medications there is an increase in the levels of some molecules called leukotrienes. Lots of leukotrienes may result in allergic symptoms like itchiness and bronchospasm [7]. These reactions occur in a very small percentage of people who have hypersensitivity to analgesics. And so it is proposed that acetaminophen and ibuprofen increase leukotriene production, and this triggers asthma development or asthma exacerbation.
The theories that link acetaminophen with autism spectrum disorder
There are several theories that try to explain why acetaminophen would increase the risk of developing autism spectrum disorder (ASD).
While none of these theories have been proven, here are some examples:
- Acetaminophen stimulates the endocannabinoid system. The endocannabinoid (eCB) system is part of our nervous system and has important roles in things like memory, learning, and emotions. This system is disrupted in children with ASD. And one way acetaminophen seems to relieve pain is by stimulating this system [8]. So the theory is that the use of acetaminophen during early childhood may stimulate the eCB system in such a way that it gets dysregulated, which could lead to ASD.
- Brain-derived neurotrophic factor (BDNF). BDNF is a protein necessary for our neurons to grow and communicate efficiently. It appears to have a role in ASD, but it’s not clear whether its levels are increased or decreased in people with this disorder [9], [10]. In rats, early exposure to acetaminophen decreases BDNF levels in the brain [11]. And so the theory is that acetaminophen modifies the levels of BDNF leading to the development of ASD.
- Fever suppression. This theory has more to do with fever than acetaminophen itself. It says that by suppressing fever, which is usually done with acetaminophen, we interfere with the brain’s normal immune development. This would make genetically susceptible children to develop ASD [12]. It’s worth mentioning that this applies to mild to moderate fevers only. High fevers that won’t go down on their own do need to be treated with medications.
Let’s see the facts. Is there really a link between acetaminophen or ibuprofen and asthma and wheezing?
Though the theories mentioned above sound scientifically valid, it is important to note that there is not a definitive body of evidence to prove these links. Most of the evidence comes from observational studies that compared babies who were exposed to these medications in the past to those who weren’t. These studies found that babies who were given acetaminophen during their first year of life were 1.47 times more likely to develop asthma and 1.51 times more likely to develop wheezing than babies who weren’t given acetaminophen [13], [14].
One problem with observational studies is that it is super tricky to prove that a child developed asthma due to the medication only. Many babies may have been given medication because they had a respiratory condition to begin with. And this condition could be the actual cause of them developing asthma in the future.
On the other hand, clinical trials that compared children exposed to either acetaminophen or ibuprofen, didn’t find any associations between these medications and wheezing or asthma [15]. One of these trials included 27,000 children under two years of age [16].
Clinical trials are much more robust than observational studies because they control for other factors that may influence whether a child develops a disease or not, besides the medication. The approach is a bit different though, because clinical trials compare children who took ibuprofen versus children who took acetaminophen. There is no group of unexposed children. But this design can still properly measure associations with disease.
Something to have in mind is that most clinical trials look at a medication’s effects in the short-term. And something like asthma may take years to develop.
More studies are needed to clearly establish if there is an association between early use of acetaminophen or ibuprofen with asthma or wheezing development later in life.
What about studies on acetaminophen and autism spectrum disorder or attention deficit hyperactivity disorder?
A small study that compared 83 children with ASD against 83 children without ASD found that those given acetaminophen at 12-18 months of age or after the measles-mumps-rubella (MMR) vaccine were 8 times more likely to develop ASD later in life. No association was found for ibuprofen [17].
Another study reported that babies and toddlers up to 2 years of age who were given acetaminophen were only 1.016 times more likely to develop ASD. And once again, no association was found for ibuprofen [18].
Finally, a very big study of more than 70,000 children from different parts of Europe found no association between exposure to acetaminophen and ASD and ADHD [19].
So while all of the evidence is not consistent, the biggest study suggests that both acetaminophen and ibuprofen are not associated with the development of ASD or ADHD.
There is definitely more research to do. Important factors to consider are children-specific characteristics. For example, one study proposed that children predisposed to suffer ASD have a metabolic disorder that would make them process acetaminophen less efficiently [20].
What to do if you use acetaminophen or ibuprofen
Acetaminophen and ibuprofen are often used to treat fever, but it’s important to know that fever is not always bad, and doesn’t always need to be treated.
Fever most often can occur as a natural result of your child’s body’s attempts to fight a viral or bacterial infection. There is reason to believe that the fever itself can be helpful in that fight. Fever can also develop in response to a vaccine, and is generally not harmful. This means that the vaccine is doing its job, and your baby's body is developing an adequate immune response that will protect them from future infections.
While there is strong evidence that these medications are safe, we believe that both should be used with caution and only when strictly necessary.
Instead, try to use non-medication alternatives for pain relief if possible.
If you do need to use acetaminophen or ibuprofen:
- Choose a brand that doesn’t contain dyes and artificial flavors. To make these medications more attractive to picky toddlers, they are often loaded with unnecessary ingredients.
They also often contain emulsifiers or thickening agents that may negatively impact your baby’s microbiome.
- Use as little as possible, and don’t use more than the recommended maximum daily dose. Make sure that you look closely at other medications your child may be receiving, as many common cold and cough preparations contain acetaminophen or ibuprofen as part of its ingredients. If you are uncertain, always ask your provider.
Do gripe water, colic and gas drops really work?
One of the most common active ingredients in gas relief and colic drops is simethicone, a generally safe medication for babies (it can rarely cause loose stools) that is used to relieve pain associated with having too much gas in the tummy.
Simethicone is an anti-foaming agent that theoretically helps gas bubbles to pass more easily through the gut. No negative effects on the microbiome have been reported.
However, some studies have shown that simethicone may not be effective at relieving colic [21], [22]. A better alternative may be fennel seed oil [23]. Some experts also suggest that probiotics can help, because your baby’s gut microbiome composition may be linked to colic [24].
These liquid medicines for babies also often contain emulsifiers or thickening agents, so if possible, choose those that are organic and free of any unnecessary additives.
Non-medication alternatives that will help your baby feel better
If your baby has mild fever or pain, there are other ways you can make them feel better without resorting to acetaminophen or ibuprofen.
Here are some important tips:
1. Breastmilk. Keep breastfeeding! Breastmilk contains protective antibodies and other compounds that will help your baby recover faster and feel better. In fact, breastmilk changes when your baby is sick to offer additional protection [25], [26].
When a baby is feeling sick, it might be easier to nurse for shorter periods of time and more often.
You can also pump milk and provide small amounts of it using a syringe.
2. Fluids. If you are no longer breastfeeding, provide plenty of fluids like water or natural infusions. Look for signs of dehydration like dry lips, no tears when crying, or fewer wet diapers per day than usual.
3. Food. If your baby is six months or older and is already eating solid foods, provide food whenever they want to eat. Don’t force food.
4. Rest. Keep your baby at home, let them sleep and rest as needed. Monitor regularly during day and night.
5. Sponge bath. A sponge bath with lukewarm water may help reduce fever. However, cold compresses or cold baths can actually make the fever worse as the brain works even harder to heat the body against the external cold source.
6. Hugs and cuddles. Giving your baby lots of love and attention won’t bring their fever down, but it will certainly sooth them.
7. For non-medication alternatives used to relieve viral ear infection, nasal congestion and cough, check the recommendations in our blog post on antibiotics for infection in little ones.
