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Similac® Soy Isomil®

Complete nutrition for sensitive tummies

Fussiness and gas can be a common part of feeding your baby.

Similac Soy Isomil is specially designed to comfort with the gentleness of soy to soothe the tummy.

Soy-based formulas have been clinically shown to help reduce feeding problems. No other soy-based formula has been studied more than Isomil.

Has OptiGRO to support your baby's brain and eye development.

If your baby’s fussiness or gas seems excessive, ask your physician about switching to Similac Soy Isomil.

Soy formulas are not recommended for premature infants with birth weights of less than 1800 g.

Similac Soy Isomil formula product for infants

Available In:

1.45-lb Powder

12.4-oz Powder

1-qt Ready to Feed

Soy for fussiness and gas

Nutrition Information

Powder / 1.45 lb

Serving size: 100 Cal (prepared as directed)*

Amount per serving

  • Calories:


  • Volume, mL:


  • Protein, g:


  • Fat, g:


  • Carbohydrate, g:


  • Water, g:


  • Linoleic Acid, mg:


Vitamins & Minerals

* Nutrient values are applicable when prepared as directed.

Similac® Soy Isomil®
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Similac Soy Isomil Reviews

Rated 5 out of 5 by from Great product We can only use the concentrate liquid the powder doesn't work well with allergies I the family. But the liquid is great and so easy to use love it so much better then powder ever! This is great for the sensitive babies :)
Date published: 2016-07-26
Rated 5 out of 5 by from Great stuff My girl's tummy can't handle regular formula. This stuff is great!
Date published: 2016-07-18
Rated 5 out of 5 by from Both of my children have been on similac soy since birth It has really great benefits and it kept the fuasiness and gas away.
Date published: 2016-07-13
Rated 5 out of 5 by from A thousand stars yes! I should really get hired by similac for how many times I've recommend similac soy! My daughter had awful colic we had tried every enfamil product out there including HA formulas. Nothing helped my poor baby! At 5 months I figured If I tried similac it couldnt be worse than what my baby was already feeling. I went out bought a tub of similac soy within 48hrs I could see the difference in her! Never had any constipation issues with this either, she goes 2-3 times a day. I absolutely love this product and tell everyone I can about it! Thanks for saving me Similac
Date published: 2016-06-30
Rated 5 out of 5 by from The best Best milk ever for my pre girl She didn't wanna eat and with this product she have done so much better. Recommended 100%
Date published: 2016-06-27
Rated 4 out of 5 by from Great but needs more options The product is wonderful and my lo has increased feeding since switching. I wish it came in multiple sizes. I see the extra large canisters (2.18 lbs.) for the other formula types. Not to mention the ready made, I can only find the 1qt and that is hard to keep cool, once open, when traveling long distance. I used to buy direct from Abbott for 2oz ready made 48 in a case which are great for travel. Occasionally I find the 8 oz. six-pack but not usually near my home.
Date published: 2016-06-27
Rated 5 out of 5 by from only formula that helped my son! amazing! My son was originally breast fed and I ended up switching him to enfamil because that is what wic covers for me. I tried him on milk based and found out his stomach couldn't tolerate it so we switched to gentlease. No relief and extreme constipation. I switched to prosobee and he was still constipated. The only formula that my son is able to go to the bathroom with and not have gas is this product. Unfortunately wic won't cover it but I would rather buy out of pocket because the product is well worth it. My son is doing amazing on it.
Date published: 2016-06-24
Rated 4 out of 5 by from Good for our little one Our daughter has a cow's milk allergy and soy formula is the only one she is able to tolerate. We tried the sensitivity one but because it's still a milk-base this was our only option for her needs.
Date published: 2016-06-21
Rated 2 out of 5 by from Bad taste bad gas My baby was very fussy on the Similar advance at first so we tried this, it gave her bad bellyaches, stinky gas and constant crying. The total comfort is a little better but I think it's the added sugar instead of corn syrup because my baby has done great on Gentleness from enfamil. I've purchased the advance, total comfort and soy and haven't received any samples or coupons to help me try any others....enfamil has sent numerous samples and coupons, that's how we ended up using gentleness.
Date published: 2016-06-15
Rated 1 out of 5 by from Didn't help! Went from Similac Advance to Similac Soy and my baby just got worst. She started off constipated with the Similac Advance. So I switched her to the Similac Soy and now she's having watery stool, she's very gasy, and is spitting up!!! And she is very fussy, this just made things worst for my baby!!
Date published: 2016-06-14
Rated 5 out of 5 by from Only formula helped baby with acid reflux! We went through breastfeeding and many formulas. Similac Soy is the only formula that my 2 1/2 month old baby was able to tolerate with having acid reflux and spitting up. We are now five months old, continuing using Similac Soy, healthy, happy and active baby. This product is wonderful!
Date published: 2016-06-08
Rated 5 out of 5 by from Baby allergy My son was getting really fussy and got a rash/eczema all over his face and head. Doctor said he is allergic to milk (formula) and put him on soy. He is doing so much better and we are so thankful. Only downfall is cost, we will only use similac, no generic, but it's definitely worth it for our child!
Date published: 2016-06-02
Rated 5 out of 5 by from Great product This is the only formula my son can use. But he can only have the liquid kind but it was an amazing change when we switched him to this instead of the blue Similac and the orange one. Totally recommend.
Date published: 2016-05-31
Rated 5 out of 5 by from this formula is the best it helped my son out very well This formula is so much better than others
Date published: 2016-05-30
Rated 3 out of 5 by from Ok formula My baby is 7 days old and was placed on SIMILAC advanced in hospital but it began to give him gas. I then switched to Similac Sensitive and still no relief. He is currently on Similac Soy and there is still no relief in the gas and still has constipation. I am so confused as to what to use yet that can digest a little smoother. I may try the Enfamil Gentlease.
Date published: 2016-05-28
Rated 4 out of 5 by from Not the best but only thing she can tolerate She still spots up frequently but she no longer forceful vomits, no constipation, and way less gas. Spit up is still a small concern and it smells bad but everything else, including Alumentum has been way worse.
Date published: 2016-05-27
Rated 5 out of 5 by from No more tummy troubles! This formula has been a life saver with one of my twin boys! My boys are 5 months old and around 4 months one of them started having lots of gas and was crying a lot with a regular milk based formula. We discussed this with our pediatrician and he recommended this product. Since then my son is doing so much better. The only downside is the cost of this formula. With twins on formula the cost is overwhelming. I wish there were coupons or rebates to help us out!
Date published: 2016-05-22
Rated 1 out of 5 by from Don't know what to do My baby has gone for Similac advance ,sensitive and now soy but her gas is getting worse and her tummy keeps rumbling like crazy and louder by the feeding she even cries out in pain don't know what else to do shes breastfed and formula fed what else can I try please help.....
Date published: 2016-05-19
Rated 2 out of 5 by from Made things worse My baby had frequent spit up on the similac sensitive and was always spitting up chunks. My ped recommended the soy and it made him even worse. He would throw up everything he just ate and it made him very constipated
Date published: 2016-05-14
Rated 5 out of 5 by from Wonderful!! This product has worked wonders for my daughter!! Galactosemia baby that can't have any milk or dairy, this product is literally a life saver. Her growth is off the charts, 96% for height and 93% for weight! Her specialist says she's the "picture of health" Thanks Similac!
Date published: 2016-04-29
Rated 4 out of 5 by from This is a good product but breast is excellent. I started breastfeeding from the beginning but ended up having to supplement. We tried Honest Co. organic, Similac organic and both left Baby with horrific constipation. Finally, we tried Soy Isomil in the ready-to-feed containers. Our only issue is the horrible smell of Baby's poo and gas. Her stool never had an odor until we put her on formula. However, we are grateful for the Similac Soy Isomil brand. Would you please consider providing organic soy formula soon? Thank you for the non-GMO samples we received this week. We won't use them because the Soy Isomil has been good for our baby's growth and development but we will certainly pass the samples on to a wonderful mom who will use them.
Date published: 2016-04-27
Rated 2 out of 5 by from Taste is good while testing some formulas to see which one is going to best for my baby girls tummy and this just made it worse, she was fussier and it seemed she was in pain trying to pass gas, when she did go it was thick and a dark green color (very dark), I probably should have gave it more then a week but after seeing her in pain i switch to similac organic
Date published: 2016-04-18
Rated 5 out of 5 by from Love Love this product. Is there anyway to get coupons??Used it with my first and started with my second child but can't afford it will have to switch to a cheaper formula. With my first child I was mailed coupon.
Date published: 2016-04-04
Rated 3 out of 5 by from Will this product cause constipation My baby have try this fomula for three weeks, some times he poo very two days and the poo are thick then before why?
Date published: 2016-04-03
Rated 5 out of 5 by from Lifesaver! We tried many different formulas for our daughter and nothing seemed to keep her happy and comfortable. For many weeks she was either asleep or fussing and crying. It was heartbreaking to listen to her cry all day. About a week ago we started Similac Soy. Immediately after her first bottle she was like a new baby. She seemed content and had smiles for everyone throughout the rest of the day. Here we are a week later and she is still doing great!. She only fusses when she's hungry or sleepy and spends the rest of the day peaceful and content. Similac Soy has been an absolute lifesaver for us!!! (I've seen several other posts about the Soy formula causing constipation our pediatrician recommended a probiotic supplement and we have not had any issues.)
Date published: 2016-04-02
Rated 5 out of 5 by from Round the clock care! Brought home our little prince from the hospital on Similac Advanced. Within a few days to a week he would continually spit up mouth fulls of his formula. No vomiting, or colic, and no diarrhea, and little constipation. The Dr, (not my normal doctor), did not really want to change his formula because he was growing so well. However, I knew this was not right. About 30 to 45 minutes after every feeding he would start spitting up mouth fulls of formula. This would continue until either he had spit up all that was left in his stomach; or until his stomach was empty enough to finally settle down. I tried burping him after every ounce, and feeding him less at a meal and more often with the same results. At the WIC office they suggested putting him on Similac Spit-Up formula. I said okay, as I had been dealing with this for nearly 3 months. It seemed to work at first, but then the spitting up started up within a couple of days. I contacted the WIC office and because he is gaining weight they claimed that he was just going to be a "Happy Spitter-Upper". Finally made a appointment with my longtime pediatrician, (this is my 9th child), as soon as I described what was happening he immediately switched him to Similac Soy Isomil. Within 24 hours of starting the Soy formula his spitting up stopped. He still has a sensitive stomach which we will watch closely, but at 8 months old he is 20 pounds 8 ounces and 30 inches long.
Date published: 2016-04-01
Rated 2 out of 5 by from Seemed to help at first... I would recommend this product to parents with a baby who has dairy issues and can handle soy. My baby was originally on Similac Neosure because she is a preemie, then she was put on Similac Spit up because of her really bad acid refllux. Then, she was put on Similac Sensitive for a number of weeks because the Similac Spitup was making her have diarrhea. But while she was on the Sensitive, she was also extremely gassy, and rarely slept at night due to gas pains and stomach discomfort. I made the switch to Similac Isomil which was recommended by her pediatrician since the thought was that she had an intolerance to dairy. It seemed to help the first 3 days. She actually took short naps at night, which she hadn't done in weeks and weeks. But, now she is right back to where she started, but worse. She is also constipated on top of all the original problems, and she is also not sleeping during the day. I am not getting any sleep either. We are both extremely exhausted. Not sure what to pick at this point. She hates the Enfamil formula, she really dislikes the taste of it.
Date published: 2016-03-29
Rated 4 out of 5 by from Gas and black stools on this I have newborn twins who have a lot of gas and were spitting up quite a bit on milk-based formula I switched them to the soy and for the last five days the spitting up is gotten better but the gas is just as bad. what happened is they are now having stools that are black they are not tarry but they were normal brown color and approximately 4 to 5 times a day on milk-based formula now they are black and only pooping once a day. is this normal for soy formula?
Date published: 2016-03-20
Rated 5 out of 5 by from Great Product, but NOW WHAT? We've used Isomil for all three of our children and it has been terrific up to 12 mos. It used to be that there was Isomil Go & Grow, but now there isn't for our youngest child. Where do we go from here?
Date published: 2016-03-11
Rated 3 out of 5 by from Still having issues We started with the similac advanced because that's what my first daughter used for 12 months. But my 2nd wasn't agreeing with it, so we switched to the similac sensitive she was still gassy, with horrible tummy pains after every bottle and was only having a bowel movement every two days which for a newborn I don't think is good. So we've switched to similac soy isomil and our daughter is still having tummy problems and it's been 5 days since the switch from sensitive. Still crying after every bottle, has horrible gas and is still only having a bowel movement every two days. I don't know what to do at this point. I was hoping it would be the cure all like others have experienced
Date published: 2016-03-10
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Has your family been affected by Hurricane Michael?

If you or someone you know has been affected, find out how Similac® can help.