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An Often Overlooked Cause of Vomiting

Most parents don't realize that not getting enough food can be the cause of unexplained vomiting in the middle of the night or first thing in the morning.

Where there is no fever, stomach flu, or any other common cause of vomiting in younger children, vomiting is often caused by low blood sugar. Most typically, this happens to children between 8 months and 4.5 to 5 years of age.

The official diagnosis for this scenario is ketotic hypoglycemia. Vomiting induced by ketotic hypoglycemia usually happens in the middle of the night or first thing in the morning, and typically when there's been a longer-than-normal stretch of not eating - missing dinner is a common cause for those who are predisposed to this.

The child will typically feel some nausea and/or abdominal discomfort just prior to vomiting, and will usually be subdued for about a half hour after vomiting, but will otherwise appear normal.

Vomiting caused by ketotic hypoglycemia is often misdiagnosed as the stomach flu. The distinguishing feature of ketotic hypoglycemia is that the child quickly returns to normal; if vomiting occurs in the middle of the night, after a short period of malaise, the child will typically sleep comfortably for the rest of the night; if vomiting occurs first thing in the morning, within about 30 minutes, he or she will be ready to eat and go about everyday activities.

Vomitus is typically bubbly and tinged with a bit of yellow color - this is distinctly different from vomitus that accompanies the stomach flu, which usually includes incompletely digested food.

Normally during night-time sleep, the body uses blood glucose and some stores of glycogen in the muscles and/or liver to generate energy needed to carry out basic metabolic activities. Ketotic hypoglycemia tends to occur in young children who either miss dinner or eat a smaller-than-usual dinner and are in a rapid phase of growth where their need for fuel is greater than what a small meal in the late afternoon or early evening plus glycogen stores in the muscles and liver can provide; this is why vomiting from ketotic hypoglycemia typically only occurs in children who have a leaner-than-average build.

How to Prevent Vomiting Caused by Ketotic Hypoglycemia

Where ketotic hypoglycemia is identified as the cause of a child vomiting at night or in the morning, treatment is simple: Just ensure that your child has a healthy bedtime snack to avoid having his or her body go more than 10 hours without food intake.

Differential Diagnoses

There are many causes of hypoglycemia, as well as causes of vomiting at night that are not related to hypoglycemia, so in cases where it's not obvious that lack of food intake in the evening is causing ketotic hypoglycemia-induced vomiting, it's prudent to have your physician fully evaluate the situation to rule out other potential causes.

Stomach flu, food "poisoning," severe coughing, a bladder infection (will be accompanied by a fever), and some type of intestinal obstruction are the main differentials to rule out.

Almost all children that experience vomiting caused by ketotic hypoglycemia grow out of it as their body mass increases with age and their ability to fast during bedtime sleep improves.

Please consider sharing this information with parents, grandparents, and elementary school teachers in your life. Being aware of this potential cause of vomiting in younger children makes it natural to understand that having them miss dinner isn't a good choice in punishment for misbehavior - it's wise to have other effective consequences ready in mind where some form of discipline is indicated, as vomiting is always best avoided for its negative effects on overall health.


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My two girls both had this when they were little and I put it together that it was probably low blood sugar. Now as teens they refuse to eat in the morning - they still feel like they want to throw up. I have let it slide because how do you make someone eat who feels nauseous? I never thought to try a before bedtime snack. I will give it a try. Thanks for the article.

If your child is vomiting without an explanation, don't look over neurological issues as well. My son had a cancerous brain tumor. I'm not trying to be a pessimist here, but for parents to be aware these things can happen. He vomited for months inexplicably, pediatricians prescribed migraine meds, until I finally realized it was something bigger and insisted on a CT scan. I always wonder, if I would have figured it out sooner, would it made any difference (such as size of the tumor being smaller and easier to resect). I'll never know.

My son also had a cancerous brain tumor. I too cringe everytime I read or hear about morning vomiting. I wish that it was more well known that this could be a symptom of something serious. If you don't feel the doctors are right...push for a are your childs best advocate.

Hi there, I am so sad to hear your child had a brain tumour. My three year old daughter is vomiting when she wakes in the morning and is then fine for the rest of the day. I have persisted with gp and a and e, they said all her neurological tests are fine and not indicative of any brain tumour. She has slight drooping of her right lip but has just had chicken pox and the diagnosed Bell's palsy after it. Did you child have any other symptoms and how where is neurological checks?
I really hope you will reply I am so sorry about your I am sure your information will help a lot of people
Kind regards Lynsey X

My son will be 3 next month, he also started vomiting late at nite or early mornings, he could eat at 8am and be perfectly fine, but then always 12 hours later vomit , Dr ruled out blockage and said it was a virus ( stomach bug .... I said he has no fever or other symptoms, and this has been going on for a month.... )I'm now pushing for CT scan since reading your story, thank you .

My daughter has had a few episodes of early morning vomiting. Occurred a couple of months ago, lasted for a couple of weeks, stopped for 2 1/2 months. It has started again this past week. She has no other symptoms (headache, blurred vision, etc.) that I can tell. Did your sons have any other symptoms besides the vomiting?

This sounds exactly like what's going on with my one year old daughter. Have you gotten any information since writing this?

My daughter has been through this, on and off for the past few months. I wonder how frequently this occurred with your little one? Did they exhibit other symptoms...headache, seizure, etc?

What were his other symptoms? My son vomits in the morning but seems fine after? Is there anything I should be looking for?

Hi there, I am so sad to hear your child had a brain tumour. My three year old daughter is vomiting when she wakes in the morning and is then fine for the rest of the day. I have persisted with gp and a and e, they said all her neurological tests are fine and not indicative of any brain tumour. She has slight drooping of her right lip but has just had chicken pox and the diagnosed Bell's palsy after it. Did you child have any other symptoms and how where is neurological checks?
I really hope you will reply I am so sorry about your I am sure your information will help a lot of people
Kind regards Lynsey X

Was the vomiting a daily thing or just random like about once a month?

She is three and on and off for months wss vomiting either while asleep or in morning. Sometimes during the day. Last night she scared me and said she wanted to go home but we were at home. What were some other things you noticed if yoh don't mind me asking

I know this is an old comment but I wanted to say thank you. This hadn't came up in a Google search but after I put in brain tumour - morning vomitting it became clear. Had I not seen this I would not have persisted an MRI for my daughter (4 years old) and discovered a high grade brain tumour. Our world's have turned upside down but she has had the tumour removed, completed radiotherapy and about to begin chemo. Thanks to this comment it had not spread. You've raised awareness for at least our family a sincere thank you and my heart is with yours x

Interesting... this is true, but I didn't know that it was due to low blood sugar. I always thought that it was wind in the stomach (all that rumbling!). When wind tries to push itself up, you feel nauseous. A little food settles the stomach quickly.

My 3 year old has been vomiting/complaining of upset stomach for three days now. It's winter break, and all my kids' sleep and eating schedules have been crazy. I just now made this connection, as I too used to not eat in the morning because of my stomach. The only difference is he's having his issues in late afternoon, but he's used to afternoon naps and snacks that we've been skipping. I'm going to try going back on schedule tomorrow. Hopefully that does the trick, or we're off to the Dr.

I see a mum on here mentioned how she two feels nausea in the mornings an I two get that way but never bothered finding out why when it first started because I've never eaten in the mornings an at that the time I was on the bigger side of 114kgs an along with nausea was feeling fuller when it came to meals I'd only be able to eat half of what I normally had an ended up going down to 110 kgs without trying and I found out I had ibs (irritable bowel syndrome) now I get the full stomach spams etc but it started with the nausea. But as a mum on the other hand I have a now 4yo daughter who has had this on n off for a few years I didn't take her to the Dr cause of how well she ended up been in the morning. But with a large enough medical history I've had with my girl I've come down to two of my own reasons why this could be an it goes on the numourus hours spending on Dr Google in the pass one been my girl knewst to suffer from diarrhea an she had over all good health no signs of bugs an Dr had no idea why an it was Google that suggested she could have to much sugar in her diet an a certain compound in sugar can be hard to digest in young kids causing vomiting and/ or diarrhea. Once I took sugar out of her drinks it cleared up. An the next thing it might be is how it is ur child sleep at night my daughter is a mouth breather due to enlarge adenoids which she's having an op on to remove she swallows in allot of air and mucus which sits in her stomach an she then vomits once in the night so if ur kid snores or u notice is a mouth breather get those checked out but I'm hoping if the op stops all this she might get to feel normal again. So yeah that's just my thoughts

I am so happy to find this page. This fits my child to a tee. She is 5, very active, and in the 2% weight range for her height. She is a picky eater. As I reflect on the day I am sad to think how little she ate. Wow. I hope we make it through tonight and I will try night snacks starting tomorrow. I hope this is the fix I have been looking for. Thank you so much.

I didn't know people still used this type of punishment!

Sometimes my 4 year old will not eat her dinner because she does not like it or is too distracted to eat. I've often been conflicted on how to handle this. I do not believe in making another special meal as I believe that sends the wrong message. I have told my child that this is what we're having for dinner and that's all there is. I will however offer some yogurt or small snack closer to bedtime if she's eaten nothing at all. I have a hard time sending her to bed with no food in her belly.

Your comment gives me a chance to ask a question I've had for a long time:
Do parents who require their kids to eat foods they don't like prepare and eat foods that they themselves don't like to eat as well?
My parents always asked my brother and I to give a little taste to everything on the plate but didn't require us to eat things we found distasteful. Today I have no problems trying new foods or eating a variety of meals. Honestly, there isn't a taste I find disgusting. (And I grew up in Asia, haha)
Conversely, my husband was forced to eat foods he couldn't stand when he was a child and now refuses to eat many kinds of foods. For instance, he never makes himself eat liver and onions now (even when it's served as dinner at his mom's) because he couldn't stand it when he was a kid.
So yeah, I've long wondered if parents make themselves eat foods they don't like because they're "healthy" or they want the kids to be thankful for what they have. My kids are now grown but once they were old enough to be active participants in the kitchen, they've had a say in what we eat and helped prepare meals. They've always been welcome to get in the fridge and grab things like carrot sticks and homemade hummus or an apple. Today they eat a variety of whole foods mindfully. I think it's good that you give your little one a chance to have a snack if she doesn't eat dinner.

Unless it is a food the majority of the family does not like (then we just don't have it) I will eat things I dislike because I want to set that example for my children. I greatly dislike peas but the rest of my family likes them and I do eat them as well. I have also done things like make 2 vegetables and you can choose which or both to eat. I won't make a full special meal for one member but I do provide choices and I always ask that everyone at least taste it. I do not force finishing off foods the kids (or picky husband!) Dislike. They don't really fight tasting foods because they see my husband and I eating foods they dislike as well.

This breaks my heart as a child who was a picky eater and probably drove my mother insane... I was sent to bed without supper regularly and cried myself to sleep because my mother would not let me eat a peanut butter sandwich for dinner instead of her lousy cooking. No offense to moms, I am now a mother of a picky eater myself, and it drives me crazy too! But I won't put my kid to bed hungry.
I have severe hypoglycemia now which is partly from my addiction to candy as a child, but I'm sure being sent to bed without dinner three nights a week could have played a hand in it as well.

Anyway long story short, it turns out gluten intolerance runs in my family and out of us six kids, only one has not been tested and the other 5 of us are all gluten intolerant. Now that I know that and I look back on my child I realize the foods I didn't want to eat for dinner were things like my dad's special breaded chicken (I always hated the floury coating), and anything my mother cooked because to be honest she was a horrible cook.

So if your kid is that picky that often, maybe you should have a look at their diet and see if there is something affecting their appetite. My daughter always gets pickier when her father buys her yogurt cups at the store. I would prefer she was dairy free but it is hard when your husband is a pushover to his little girl...

Anyway, don't punish your kids by starving them. I have suffered from my mother doing that to me.


My daughter had a seizure 3 weeks ago which included a vomiting episode at 5 AM in the morning. Took her to the ER and they checked everything ... blood, urine, CT scan, EKG .. everything was normal. Only problem was that with the blood test ... we had given her orange juice on the way to the ER at the recommendation of an EMT that came to our house that morning. So the blood sugar test would have been skewed.

The weeks following the seizure she began randomly vomiting at about 2-3 AM. I thought, initially, that maybe it was a touch of a bug but she had not one other symptom, no fever, nothing.

About two mornings ago she woke up at 3 AM and said "I'm hungry." and then a few moments later she vomited. I couldn't go back to sleep so I began googling and found this article. Everything clicked into place. She is very slender and I had a feeling she was going through a growth spurt in the past few weeks as she has been eating "like a horse".

I just got back from the pediatrician's office where we confirmed she had a fasting blood glucose level of 44. Low. Doctor is now testing insulin and other things.

But I just wanted to say that this article really made a HUGE difference for me and my daughter. A life saver I would say. I don't think I would have made the connection otherwise.

Does your daughter have a seizure disorder also? Or was the seizure brought on by the blood sugar level? I could have written your post word for word describing our scenario. VERY interesting! What was the solution? Any information you have to share would be VERY helpful!

My two girls suffered from this but like another poster - only in the mornings. They are now 20 and 15 and still will not eat breakfast before 9am very often. I had read about the low blood sugar connection but couldn't get them to eat anything in the mornings even tho we knew the cause. My oldest turned out to have a very strong insulin response as we had a oral glucose test done and it was flat - her fasting BG was 85 and didn't deviate more than 5 points over the two hour test. She subsequently has to eat frequently and eat lower carbs to control the nausea and weight gain. Doctors told us if she didn't do more to control her insulin she'd be diabetic at an early age. 7 years later no diabetes but she did develop PCOS which is also related to insulin problems. The bedtime snack should help most kids.

My son will be 4 this year. I started realizing the late night. And early morning vomiting as well. But my take is hes always eating he loves his food or even if I don't give him cook food he will have his hawlicks tea before Bed. He drinks slot off juice and water. He not much of a fan for snacks. But yet when I too him to the doctor I was told that he has infected diarrhea. Including off when vomiting all I see is foam or he had dinner late so he vomitted up some of it. But other night when he have just his tea all I see is foam. It's like while he's vommiting he.shacks while he forceing something to come out and all I see is foam. He uses the bath too often to and he cries for his belly alot.

Can someone please help me with my 10 year old sister she recently turned 10 she started out the day normal and after dinner she would run to the bathroom and would throw up and she would have stomach pains i have given her medicine she has been sick since the day before her birthday and right now her stomach really hurts right now so if anyone can answer what is wrong with her i would really appreciate it very much thank you very much

Aubri - it is difficult to speculate on what is causing your sister's vomiting. I hope that your parents can take her to your primary care physician for a thorough evaluation. I'm sorry that I can't be helpful in this case.

Ben Kim

Thank you for this article. My 7 month old baby vomits every single morning at 4am or 430 am. She will retch and throw up clear liquid or bright yellow bile. This will last on and off for about an hour and then she will eventually go back to sleep. She is 100% G-tube fed and her last meal is at 9pm. Her next meal is at 6am. I have tried feeding her at midnight and 1am and she still vomits at the same time. Should I try a 3am feed? Doctors don't have any suggestions.

Hi Jennifer,

I would try a feeding at 2 if you are able to manage it. As your daughter grows and gains more mass and is able to eat more per meal, this issue should resolve.

I hope the extra feeding at 2 is helpful.


Our daughter finially made her First Communion at 14 with the 7 and 8 year olds.That sunday morning,we had a nice breakfast and i noticed was somewhat nervous.After breakfast,she got in the bath tub to take her bath while i laid out her communion outfit.After her bath she came into her room and was shaking some.She laid down on her bed and i then pinned her cloth communion diaper on her then put the rubberpants on over it followed by her lace socks and shoes.She was sitting there while was getting her dress ready when all of a sudden she thru up all of her breakfast!She got the front of her undershirt and the rubberpants,so i had her take them off and quickly washed them out and put them in the clothes drier quick.She told me that she was quite nervous and paranoid about wearing the diaper and rubberpants and undershirt under her dress and thats the reason she thru up. I told her that it would be fine and that she would be just like the little girls in her class.I got her undershirt and rubberpants out of the drier and put them back on her and finished dressing her.She didnt have any more problems the rest of the day!

I found this article about 2 years ago or so. It explained everything for my son and helped me to be able to sleep at night. He used to wake up in the morning crying that his head hurt and then would throw up after about 30 minutes to an hour. Then he would eat and be fine. Hes always been super picky and a very slow eater, but at the time I just thought he wasn't hungry. It only happened every so often and to me, it seemed random, until I found this article. I noticed on nights where he was estatic about our meal (aka it wasn't chicken nuggets) he would wake up crying and throw up and then eat and then be fine. Once we went 2 hours longer than normal before eating dinner and he started crying out of no where and threw up. I got him to eat a little and he was fine. I started giving him snacks and extra milk right before he went to sleep. It helped a lot. He's 6 now and no longer has issues like that. I just started carrying around extra snacks in case we were going to be out and go longer than a couple hours without food.

My son vomited -often at night. If he over ate it was more common, but not always. After I put him on probiotics he never vomited again at night or when I was driving him.

Dr. Kim, I was so grateful to come across this resource. Our 9-year old son was throwing up every morning between 3-5AM for a week with no other symptoms. It seemingly came out of nowhere and there were no answers. The doctor just said it was a probably stomach bug but thought it was strange it would only present in the wee hours of the morning. He was exhausted the rest of the day but could eat and function after he threw up multiple times and then slept for an hour or two. After reading your article, we had the doctor test for ketones which were present. That evening we started making sure he had food in his stomach before going to bed. The next morning and the following ones, no vomit! He is growing so quickly right now and is lean build so that all started to make sense. We are primarily vegan at our house and eat a healthy diet, and I always thought it was better not to have a full stomach before bed. But, this seems like the perfect storm and the rules have to change! We are grateful he is feeling better and that we could get to the bottom of this.

I'm so glad to know, Meredith, thank you for sharing. I trust that your son will continue to thrive in the years ahead. - Ben

I have a 5 yr old little girl who occasionally vomits like this article says. She wakes up complaining her throat feels funny and will vomit clear bubbleish yellowish liquid within 30min or so. This only happens in am. After seems fine rest of the day. She’s also been complaining of abdominal pain off and on for 2 months now. Pediatrician and GI specialist say it’s reflux and prescribed Nexium. Xray, ultrasound, labs have been normal.

This sounds very similar to what I am experiencing with my 2.5 year old daughter. She is sick maybe 3-4 times a month, randomly in the morning, normally on the way to take her brother to school. She is a very poor eater and sometimes goes all day without eating. She complains a lot about her tummy hurting. I have booked her in to see the doctor after reading this article!
Have you found that the reflux medication is working for your daughter?

At about age 4 my daughter began frequent vomiting the in teen years in morning. Many tests and medical oversight did not revealnthe cause. She began gaining weight. At age 25 she had bariatric surgery to lose it. This resulted in end to vomiting. but not her brother’s jokes about t his memory of her throwing up in mall, IHOP and on Santa Claus or her vomiting being like terror i attacks. Not sure why the surgery ended the vomiting. I know most will say she was over eating but a glass of water seemed to add pounds to her. A pediatrician removed me of guilt of over feeding her. Her siblings were in normal weight for age. I believe it was something to do with small intestine because this was cut in surgery. She is now 48 and physically and mentally healthy

I am curious to hear what others and Dr. Ben Kim has to say in response to this question. I was a child who began throwing up bile every morning at the age of 4 years. And I went on to do so for the next 2 to 3 years. I was nauseous all day long, a belly ache and threw up especially under stressful situations. Everyday in school, mostly. The nausea and bellyache continued after school as well. I had abusive teachers (they hit me for vomiting in class and I was also sleepy a lot and fell asleep in class) and my family had its dysfunctions too. My parents went through a rough patch and fought a lot. There was a lot of yelling and arguing at home. Not to mention but I come from a large family with 7 siblings, of which I was the second to last in birth order. So, there were many times I felt alone and depressed. Like no one cared.

Around the same age of 4 yrs, I also displayed skin problems that are found in people suffering from insulin resistance namely acanthosis nigricans. It was most prominent on my neck.

I am now 45 years old. I have had weight problems for the last 40 years. I have lost weight 4 times by starvation and exercise but the damned weight always seems to come back. I am frustrated with the situation, to say the least. I was diagnosed with PCOS in my teens because I developed hirsutism as soon as I hit puberty.

I wonder if there is some relation between my childhood vomiting, environmental stress, and my insulin resistance which has led to my weight problems. I was taken to many doctors, numerous x-rays and tests. But, they never found anything wrong with me. Perhaps, it is something inside my body that was never really addressed, or perhaps it was psychological? Whatever it is, I still seek a solution to my weight problems.
Any insights?
Anyone experience the same and had some info to share?