What if a baby is suddenly throwing up all formula? The baby in this Q&A has not had a changed diet but is still throwing up every time she eats.

Let’s take a look at what may be the cause.

baby throwing up formula all of a suddenPin


Mom’s Question:

My 5-month-old has all of a sudden started throwing up all of her formula. We haven’t changed anything from the day she was born, she eats Similac Advance.

She seems to be feeling fine other than the vomit, but she starts spitting up from the minute she’s done feeding, and it continues until her next bottle. (about 3 hours later)


Why A 5-Month-Old May Suddenly Spit Up More

There are a number of reasons why a baby may start vomiting all of a sudden, even without a change of diet.

Cold or Other Infection

Has she had a cold lately? Some babies throw up easily, and mucus mixed with the formula may make them throw up long after they are actually ill.

Other possibilities are a stomach bug, ear infection, or urinary tract infection, but in these cases, you would notice other signs of illness as well.


She is not constipated? Some babies may throw up their formula due to constipation. 

Some signs of constipation are not pooping for several days (longer than usual), gassiness, straining, and small, hard poop. 

Other Reasons

Then, of course, you have acid reflux and milk protein allergy, although both of these should probably have appeared earlier than at 5 months.

Actually, I’d probably talk to a doctor. Is your daughter spitting up or really vomiting? If this continues for more than a day or two, talk to a doctor, even if your girl seems healthy in all other aspects. No point in taking chances when it comes to a little baby!

Also, watch for signs of illness, of course, and of dehydration.

Good luck!


More Babies That Vomit

Find comments below.

Comments for “5-Month-Old Suddenly Throwing Up All Her Formula”

Jan 23, 2017 Please help

by: Jamie

My son has had the same problem. He was doing fine on Similac Advance Ready to Feed on birth to 5 months and suddenly started this. Has been to the dr. They have tried him on several different types of formulas (Similac Advance which he’s been on since birth till 5 months, Similac Soy, Similac Sensitive and now Similac Alimentum) and he still takes his bottle (cut him back from 7oz 4x a day to 5oz 5x a day) and he still gets puffed eyes, gags some, and throws up a month to 2 mouths full almost every bottle. The doctor has now put him Simply Thick to thicken his formula which cut it down some, to about a mouth full but is still gagging and so on off and on till his next feed. My son does have a shunt of water on the brain at birth but has had a CT scan done, Should I ask the dr to go a urinalysis (I know I misspelled). PLEASE if anyone can help. Thank you!

Feb 05, 2017 same issue

by: Anonymous

My son is 6 months and the same issue. He is breastfed and a few bottles here and there. It seems like every time he gets a bottle he throws it up. He used the Similac ready to feed in the hospital after he was born because he had low blood sugar. I am going to try good start-I used that with my daughters and they seemed to do better.

Mar 29, 2017 Think we might have a Milk Intolerance

by: MyloEmma

My son just turned 5 mos. and yesterday and today he has been spitting up more than usual (2-3 times between 4 hr. interval feedings). It’s hard to say what it is exactly since he has been on carrots for a week, and has graduated from rice cereal to the mixed rice/wheat cereal. He has had bad cradle cap that I’ve been keeping in check with “cradle cap care” but doesn’t seem to be clearing up and is reminiscent of what a previous post deemed a “rash in the forehead area”. He started out on breast milk but my production was not enough and he was supplementing with 2 oz. of Enfamil every feeding (per my lactation consultant) and after his first 2/3 mos. of life I still was not producing enough, it seemed I was supplementing with breast milk instead and weened him to strictly Enfamil premium. I tried Similac Alimentum, but it made him gassy. So we’ve been using the Enfamil premium and his throwing up has just become a problem. I will be trying the Similac Soy Advance with his next feeding and hopefully, this will negate his spitting up. He is a very happy baby, otherwise, and if no change for the better is seen with using a soy product, I will be checking with our pediatrician regarding the corn syrup allergy. I will post again with any changes…

Oct 11, 2017 My 7 month old throws up without oatmeal in her bottle

by: Ashley Moore

My 7-month-old daughter cannot keep formula down without oatmeal we have tried every formula and nothing has worked she has had oatmeal in her bottle since she was 2 months old cuz its the only way she can keep her bottle down. We have been to the dr and he said she had acid reflux but he said it would go away at 5 months. I believe it has but still, she cannot have a bottle without oatmeal. I’m at my wits end with it. Were on wic but they only give us 3 small boxes a month and that’s not enough and buying a few boxes each week is getting expensive.  Thank you

Oct 12, 2017 Being 7 months old and still throwing up

by: Paula (EasyBabyLife)


I don’t know why your Dr told you that reflux disappears at 5 months or maybe you misinterpreted what he said. It can go away at that age, but it can also continue a lot longer, even after the first birthday.

It is great that you have found oatmeal to help. Does solid food help too, if you have introduced it yet? For most reflux babies solids are a lot easier to keep down than formula.

If you have reasons to believe that your baby’s reflux really is gone, and she can still not keep the formula down, you might want to look into if she is sensitive to the lactose or milk protein in the formula. Have you tried soy formula, lactose-free formula, or hydrolysate formula? Any of these may help her if she would be intolerant to lactose or allergic to milk protein. Some babies are allergic both to milk and soy protein, and in such case, a hydrolysate formula can really help.

Also take your baby back to the doctor – or to another one, especially if she seems to be in pain of isn’t gaining weight as she should.

I hope this helps,


Nov 09, 2017 no soy for boys

by: Anonymous

DO NOT GIVE YOUR BABY BOYS SOY FORMULA! The soy messes with their hormones!!!

Jan 22, 2018 9-month-old boy suddenly throws up formula in sleep.
by: Anonymous
I have a 9-month-old boy which is a very happy baby. He has never had any problems except as a baby he had colic. Today he has grown out of that stage and ready to explore. Last night he begins to throw up formula out his mouth. The amount off formula didn’t seem normal to me. He is currently on Similac Alimental. I’m not sure if this is serious or not? I pray that it is not a stomach virus. He won’t drink any of his formula and I’m sure he is hungry. What should I do? Has this happened before to anyone else?

Apr 11, 2018 baby throwing up

by: Anonymous

It seems to me that a lot of the babies that are throwing up like this are on Similac, that’s what my daughter is on! My daughter is 8 months old and this has happened for the 3rd time that she has projectile vomited up her whole bottle…in a span of time tho. She gets very very weak and wants to go right to sleep, she was on what they call Baby Zantac till she was almost 4 months old and had to take her off because it caused her to have belly aches badly…but she was fine up until recently when I noticed she is spitting up more when she is on Similac sensitive as well…she is teething and I didn’t know if that could be a symptom or part of her doing this or is her reflux acting up again..any suggestions? I’m calling the doctor tomorrow!

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  1. Asdfg

    My older son started refusing his formula and gagging and throwing up around 3 months. I have no idea what caused it. It was horrible. We started him on solid food at 4 months by doctor’s advice. He refused that too and kept gagging and throwing up. I cried so much about all this. At 2years if age he started having sleep apnea problems and his tonsils seemed huge. He was a happy and energetic kid but refused to eat and gagged and vomited. He was on no medications. At 3.5 years old we got his tonsils removed and our feeding problems ended the day of the surgery, no kidding. I still don’t know what caused it and if he grew out of something, or was it the surgery?!? Hope no one has to deal with such problems for long!