Why Are My Dr. Brown’s Bottles Leaking? (8 Reasons Why & 3 Ways To Fix It)

There are four components to Dr. Brown’s bottles; the bottle, the vent, the nipple, and the collar, which need to be fixed properly. Leakage occurs when the nipple type is incorrect, leading to slow flow levels and pushing air into the vent, which builds pressure that pushes milk out of the collar. Proper assembling, nipple size and age, the baby’s feeding position, and the formula or breast milk temperature should all be considered to fix issues with leaking. The incorrect assembly of the bottle’s venting system will lead to untold leakages.

The most common problem that mothers face with Dr. Brown’s bottles is leakage.

They start to leak during preparation, feeding, and even while traveling, wasting away your precious breast or expensive formula milk.

Not only will your little one be covered in milk, but this also deprives them of the nutritional value present in the milk. Regardless of their messy, leaky status, Dr. Brown’s bottles are common in many households with babies.

Why? You may ask.

Because their venting system helps reduce colic, gassing, spit-ups, and burping. 

The good news is that this leaking is common, and the solution could be as easy as not buying a new Dr. Brown’s bottle. It is not unusual for baby bottles to leak, but why Dr. Brown’s?

Why is my Dr. Brown’s bottle leaking?

Figuring out why your baby’s Dr. Brown’s bottles are leaking is a bit of a trial-and-error process.

Here we make it easier for you to pinpoint where the problem is, as your little one still needs to eat while you are still figuring it out by yourself.

1. The bottle is leaking due to the vent system

The ventilation system in Dr. Brown’s bottles consists of two parts that fit perfectly into the bottle. This system pushes air to the back of the bottle, thereby reducing business in babies by preventing gas.

While this is the main attraction to these bottles, it’s also the primary reason they are prone to leaking.

2. The bottle’s collar is not perfectly tightened

The bottle collar can not be too loose or tight, or it will leak.

This is because the vent seal will be broken. That is the seal between the round part of the vent system and the bottle collar.

3. Using the bottle without the vent system 

When you attempt to use Dr. Brown’s bottles without the vent, they will start leaking.

If you are trying to use them without the venting system, put the vent system back to cure the leaking problem.

4. The bottle was heated with the vent system in 

While we are not supposed to heat bottles in the microwave, occasionally, we’re in a hurry, or for whatever reason, there’s no hot water.

If the formula gets too hot and rises into the vent system, it will cause leaking issues.

Don’t heat the bottle with the vent system inside. Instead, heat the formula, then put the ventilation system in the bottle before feeding the baby.

Heating the formula in the bottle on the stove with the vent system tucked inside will still have similar results.

If, by any chance, you’ve heated the bottle with the ventilation system in place, then pour the formula into a different bottle.

5. The bottle is leaking because the formula was mixed with the ventilation system inside

Most of the time, we mix up the formula in the bottle by putting it in the water, adding the scoops of the formula, and then shaking up the bottle. 

Dr. Brown’s bottles will cause a leaking problem if the formula gets stuck in the vent system. Instead, mix the formula without the vent system in place, then replace it before feeding your baby.

6. Ignoring the fill line

It is essential to pay attention to this because it is very easy to mess up this part.

For example, if you fill the bottle and then add powder, the result is that the formula mixture ends up going past the fill line.

If your little one is drinking bigger bottles, you may have to make them two separate bottles to avoid overfilling Dr. Brown’s bottles.

7. Not allowing the bottle to dry properly

Even though it is impossible to get every component of Dr. Brown’s bottle dry with a towel, it is important to ensure that each component has plenty of time to dry.

A bottle rack will ensure plenty of airflow to all parts of the bottle. If they aren’t completely dry, it can result in the bottle leaking.

8. Using incorrect nipple

An infant boy is drinking milk from his bottle

It seems as though anything can break the vent seal on Dr. Brown’s bottles and cause leakage, and one of those things is using an incorrect nipple.

If your baby is ready for a medium-sized nipple yet they’re still on a slow-flow nipple, the result will be them sucking harder, breaking the vent seal, and the bottle leaking.

You should double-check the age of the nipple you are using and watch for signs that it’s time to switch to a different nipple size.

Solutions to a leaking Dr. Brown’s baby bottles

Even with the new leakproof designs cropping up, there’s always a high likelihood of leaks and spills. However, there are different solutions to a leaking bottle; the answer to the problem will vary between situations. 

1. If the bottle is leaking while preparing 

Do you notice any leaks when you are busy mixing and shaking the formula or warming the bottle to get the temperature right?

The leading cause of this is the change in pressure. Therefore, you should remove all the parts of the bottle when prepping the baby’s milk.

Use a travel cup instead of a collar and nipple. You can also loosen up the collar of the bottle. This helps in releasing any pressure while warming the milk.

2. If the bottle is leaking while feeding 

Is your bottle only leaking while feeding your baby? There’s a high chance that the nipple flow is the culprit. It could either be too slow or too fast for your little one.

When the nipple flow is low, babies will suck harder than usual, which pushes air into the vent, leading to the build-up of pressure.

On the other hand, high flow pressure pushes the milk out of the collar resulting in an equally bad leak.

So what to do in this situation? You need and should increase the nipple flow to a level that your baby will not struggle with when feeding.

3. If the bottle is leaking while traveling 

Traveling with a baby is hectic in itself. Then you have to deal with a leaking milk bottle too? Well, not anymore.

It is best to ensure that the bottle stays upright as long as the nipple, collar, and vent are on.

If you are traveling a short distance, keep the parts of the bottle on and keep the bottles upright.

If the journey is long-distance or you are in an environment where you can’t keep the bottle upright, remove the parts and then close the bottle with a storage travel part.


Is that a straw in Dr. Brown’s baby bottle?

No. That is not a straw.

It is a vent tube connected to a reservoir and is the part that allows air to enter the bottles and be directed to the area above the liquid, keeping the liquid and the air separate.

What to do if I’ve lost a part of the vent?

If you’ve mistakenly lost any parts of the vent during cleaning or while traveling, replacement parts are available here.

If you are having difficulty finding the reply parts you need, then you can place a call to Dr. Brown’s customer service team.

Is it necessary to only use Dr. Brown’s nipples on my Dr. Brown’s bottles?

Yes, it is. Dr. Brown’s bottles are fully vented, requiring a unique teat.

Other bottles have a vacuum inside that restricts the flow of liquid, and because of that vacuum, the teats on those bottles tend to have a very large hole.

Thus using one of those teats on a Dr. Brown’s bottle could result in feeding your little one too much, too fast, possibly causing your baby to gag or even choke.


Despite the sensitive vent system that results in leaks, which is the number one complaint about these bottles, most parents agree that Dr. Brown’s bottles are the best because they make it easier for babies to feed naturally, just like in breastfeeding.

They are better for babies’ digestion and recommended for children with colic, especially because they’ve been proven to reduce gas bubbles and acid reflux, invalidating the aforementioned leaking problem.

Was this article helpful?

Hello, I am Emelda from Nairobi, Kenya. They simply call me mama Lilly. A fun of long road trips and a very good cook, along with my mommy duties to a super active girl. She inspires and challenges me in equal measure, and that is how I get to share with you our journey of triumph as we grow and tag you along.

Leave a Comment