Marci Kids Study

Watch this video from the creator of the MarciKids study!


Marci Kids Study page explains the principles of PPI treatment in infants and small children and why they work if they are dosed properly That's the difference between our success when other PPI treatments have failed.

Jeffrey Phillips Pharm D., the lead in the study explains it in the video above.

The “MarciKids Study" was a three center study ( done at the University of Missouri and two other centers) performed by a group of physicians, nurses and pharmacists that specialized in infant GERD.

The basis of the study was, that because infants and small children metabolize many medicines (including PPI medicines) much faster than adults, infants and small children required higher doses, more frequently to control acid reflux disease symptoms.

PPI dosing in infantsUp to date is publishes the most recent findings in the medical industry. This article on PPI dosing in infants 8-2019

UpToDate is a subscription resource exclusive to medical care practitioners that are interested in the most recent and verifiable treatment studies and science based medicine.

Marci Kids Study - Terms to Know

PPI stands for proton pump inhibitor and they block the production of acid at the parietal cell where production occurs. PPIs can only block the proton pumps that are active (producing acid at that moment). If the pumps aren’t producing acid then the PPI has no effect.

A drug regimen is the drug that you take, how much you take per dose, and how often you take it, and the length of treatment is in duration (number of days, weeks, months etc).

Half-life is the time required for the drug concentration in the bloodstream to drop by ½.

Does that make sense so far?

The graph below, created during the Marci Kids Study, shows the half-life of lansoprazole compared to age in infants and children. As you can see there is a relationship between age and half-life with some degree of variability. This is important to consider because half-life effects the acid inhibition in PPI medicines.

lansoprazole half life chart as it relates to infants with acid reflux

Tran A, Rey E, Pons G, Pariente-Khayat A, d'Athis P, Sallerin V, Dupont C.  Pharmacokinetic-pharmacodynamic study of oral lansoprazole in children.  Clinical Pharmacology and Therapeutics. 2002;71: 359-367.

As shown in the graph, the estimated half-life for the child indicated here in the chart would be 0.5 hours.

The average adult takes 1 dose per day (baseline from above) to achieve good acid control, so this one year old child would be expected to need 3 doses per day. The Marci Kids study showed that infants responded best to 3 doses a day because they metabolize so quickly.

In the Marci Kids study, they calculated the dose as follows: The amount of PPI was determined by multiplying the volume of distribution and the child's weight. An example below would show a typical calculation of a PPI dosing regimen to be prescribed by your medical care team if they agree to the Marci Kids Study dosing suggestions.

3.5 x 0.2 mg/pound = 0.7 mg/pound

Some infants or children required a higher dose to control acid reflux symptoms so there may be times when your doctor would want to increase the milligram (mg) per milliliter (mL) concentration and/or the dose. We know finding the right doctor is key which is why we offer care to those looking for help in our online telemedicine appointments. You'll have the benefit of working with a medical professional that can provide you with the specialty treatment your baby needs.

PPI Regimen Used In The Marci Kids Study

It is absolutely required that you contact a doctor and work with them on any medical treatments. This chart is ONLY here to show what the Marci Kids study used as a guideline. We are not suggesting that you use these dosing regimens for your child unless a doctor is involved with treatment. If you need a medical care team connect here.

Lansoprazole Lansoprazole (Prevacid®) is typically mixed at a 3mg per ml concentration.
 Childs Age  Doses per pound of body weight  Doses per
Under 3 months old 0.7mg to 0.8mg of PPI per pound of body weight 3 times per day
3 to 6 months old 0.6mg to 0.7mg of PPI per pound of body weight 3 times per day
7 months to 2 years old 0.45mg to 0.6mg of PPI per pound of body weight 3 times per day
2 years old or older 0.45mg of PPI per pound of body weight 3 times per day
5 years old or older 0.35mg to 0.45mg of PPI per pound of body weight 2 times per day

Omeprazole (Prilosec®, Zegerid® and generic forms) and Esomeprazole (Nexium®) All other PPI drugs (Nexium®, Prilosec®, Zegerid® as well as the generic versions of Omeprazole) are typically mixed at a 2mg per ml concentration.
 Childs Age Doses per pound of body weight  Doses per
Under 3 months old 0.7mg of PPI per pound of body weight 3 times per day
3 to 6 months old 0.6 to 0.7mg of PPI per pound of body weight 3 times per day
7 months to 2 years old  0.45 to 0.6mg of PPI per pound of body weight 3 times per day
2 years old or older 0.45mg of PPI per pound of body weight 3 times per day
5 years old or older 0.35mg to 0.45mg of PPI per pound of body weight 2 times per day

Common Questions About PPIs and Marci Kids Dosing

A common question is: Can I give too much to my baby? The short answer is NOT REALLY! 

PPIs are very specific in where they work in the body and are only active in a very specific place, the acid secreting portion of a cell, called the parietal cell. Since PPI drugs only work on the acid secreting cell they have generally a good safety profile. PPI drugs are known as pro-drugs because they are not active in the bloodstream. PPIs only become active when they pass into the acid secreting portion of the parietal cell (the cells in the stomach that make acid).

 This is important because we get this question a lot. Whatever the body does not put to use gets passed through the system.

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The following is a list of citations that may be helpful in obtaining more PPI dosing information in children:

*MBCHB, FRCPC, FACG. Decisions in diagnosing and managing chronic gastroesophageal reflux disease in children.  Journal of Pediatrics 2005; 146:3-12
Burnett JE, Balkin ER. Stability and viscosity of a flavored omeprazole oral suspension for pediatric use.
American Journal of Health-Systems Pharmacy 2006; 63:2240-2247.

Clinical studies showing that higher PPI doses are required to achieve healing in pediatric patients are listed here on the PPI dosing information page below. Along with them are the credits for those who participated and published these studies:
Gunasekaran TS, Efficacy and safety of omeprazole for severe gastroesophageal reflux in children. The Journal of Pediatrics 1993; 123:148-154.
Israel D, Shepherd R, et al. Omeprazole for treatment of chronic erosive esophagitis in children: a multi-center study of efficacy, safety, tolerability and dose requirements. The Journal of Pediatrics 2000; 137:800-807.
Iarocci TP, Tan H, Singer, J, Barron J, Pilzer E, Patel D, Bakst A. Proton pump inhibitors in infants.  [Abstract] American Journal of Gastroenterology. 2005; 100(suppl.):S273.

Clinical study of pharmacokinetics of omeprazole in children
Andersson T, Lundborg P, et al. Pharmacokinetics of orally administered omeprazole in children. American Journal of Gastroenterology 2000; 95:3101-3106.
Pharmacokinetic study showing the relationship between lower age and higher dosing requirements in pediatric patients: younger children require higher and/or more frequent doses due to shorter PPI half-life. The first author is employed at Astra (company that makes Prilosec.)

Reviews of PPI use in children: pharmacokinetics, safety, efficacy, and PPI dosing information
Israel DM, Omeprazole and other proton pump inhibitors: pharmacology, efficacy, safety, with special reference to use in children. Journal of Pediatric Gastroenterology and Nutrition. 1998; 27:568-579.
Specifically states that on a per kilogram (weight) basis, children require higher doses of omeprazole than adults due to different pharmacokinetics of omeprazole in children. Discusses at length the use of buffered PPI suspensions in children as a preferred dosage form.
Litalien C, Theoret Y, Faure C. Pharmacokinetics of proton pump inhibitors in children. Clinical Pharmacokinetics 2005; 44:441-466.
Abstracts by Jeffrey Phillips, Pharm.D., describing use of ChocoBase and CaraCream in pediatric patients; includes some PPI dosing information
Phillips JO, Bettag ME, Parsons DS, Wilder B, Metzler MH. Use of flavored lansoprazole or omeprazole suspensions in pediatric GERD. [Abstract A1292] Gastroenterology 2000; 118: 5904.
Phillips JO, Parsons DS, Fitts SW. Flavored lansoprazole suspension in pediatric GERD. [Abstract] Journal of Pediatric Gastroenterology and Nutrition 2000; 31:S181. [Abstract No. 707].

This PPI dosing information and chart and a portion of the textual contents of the PPI dosing information page came from the Marci-kids website.