It is one of the first questions parents ask, and it is a fair one. A neonatologist wrote the order. A NICU nurse mixed and fed the bottle. Nobody handed a parent a can of Similac or Enfamil in the hospital and asked them to choose. So if the doctors made the feeding decision, why does the NEC baby formula lawsuit point at Abbott and Mead Johnson — the companies that made the formula — instead of the people who ordered it?
The answer runs through a rule most families have never heard of but that sits at the center of nearly every one of these cases: the learned intermediary doctrine. Understanding it clears up the confusion, and it explains why the whole fight in these cases is so often about one thing — what the company told the doctor. This article walks through it in plain English. Nothing here is legal advice, and it does not predict any outcome; it explains how the law is built.
The one-paragraph version. The NEC lawsuits are failure-to-warn product liability claims. The allegation is that the formula makers did not adequately warn about the NEC risk of cow’s-milk-based formula for premature babies. Under the learned intermediary doctrine, a maker of a physician-directed product usually satisfies its duty to warn by warning the doctor, who then exercises medical judgment. So the legal question becomes: did the company give the physician an adequate warning? If the answer is no, the failure belongs to the manufacturer — even though a doctor signed the feeding order. The doctrine defines who must be warned; it is not a shield that makes the companies untouchable.
If the doctor ordered the formula, why isn’t the doctor the defendant?
Because a product liability failure-to-warn claim is about the warning, not the prescription. The law treats a specialized preterm formula fed in the NICU like other products that reach a patient only through a trained professional: the manufacturer’s job is to make sure the professional has honest, complete information about the known risks. The professional’s job is to weigh that information for the individual patient. When the information the professional received was incomplete or understated, the law looks back up the chain to the party that controlled it — the manufacturer.
That is why suing the company is not the same as saying the NICU team did anything wrong. In many NEC cases the treating physicians acted reasonably with the information they had. The claim is that they were never given the full picture of the risk in the first place. Whether a separate claim against a hospital or provider also exists is a different question, with different rules, that we come back to below.
What is the learned intermediary doctrine?
The learned intermediary doctrine is a long-standing rule in product liability law. For products that patients receive through a healthcare provider — classically prescription drugs and medical devices — the manufacturer ordinarily discharges its duty to warn by giving an adequate warning to the provider, rather than directly to the patient. The provider stands between the manufacturer and the patient as the “learned intermediary,” using professional judgment to decide what is appropriate for that particular person.
The phrase itself comes from a 1966 federal appeals court decision, Sterling Drug, Inc. v. Cornish, in which the Eighth Circuit described the prescribing doctor as “a learned intermediary between the purchaser and the manufacturer.” The idea is now reflected in Section 6(d) of the Restatement (Third) of Torts: Products Liability (1998), which frames a manufacturer’s duty as running to “prescribing and other health-care providers who are in a position to reduce the risks of harm.” A large majority of states follow some version of the doctrine.
The logic is easy to see with a complex medical product. A neonatologist is trained to weigh risks and benefits for a fragile premature infant in ways a parent cannot be expected to. The law therefore channels the warning to the person equipped to act on it. But notice what the rule assumes: that the professional actually received an adequate warning. Take that assumption away, and the doctrine does not protect the manufacturer — it points straight at it.
How the doctrine actually shapes an NEC case
Follow the chain the law builds. In an NEC failure-to-warn case, it looks like this — and the manufacturer’s duty lives at the very first link:
The manufacturer must warn the physician
The company’s duty is to give the NICU physician a complete, accurate warning about the NEC risk of cow’s-milk-based formula for premature infants. This is where a failure-to-warn claim is aimed.
The physician exercises judgment
Armed with an adequate warning, the physician weighs the risks and benefits for that baby and decides how to feed. The doctrine assumes the doctor is fully informed when doing so.
Warning causation
The family must also show that a stronger warning would have changed the decision — that the team would have, and could have, fed the baby differently. This is decided on the specific record.
That third link is why a related concept — warning causation — keeps appearing in NEC rulings. The learned intermediary doctrine tells you who had to be warned (the doctor); warning causation asks whether a better warning to that doctor would have mattered. The two work together. A recent federal appeals decision, Mar v. Abbott, turned on exactly this: the court assumed the warning could have been stronger but found the plaintiff had not shown a better warning would have changed the feeding, because that NICU had no adequate human-milk alternative to give. The doctrine and the causation question are the machinery running underneath these headlines.
It is also why a different case went the other direction on a technicality of the doctrine. In 2026, an Illinois appellate court reversed an Enfamil verdict and ordered a new trial over how the jury had been instructed on the learned intermediary rule. A reversal like that is not a ruling that formula is safe; it is a ruling about getting the doctrine’s wording exactly right for the jury. That these cases rise and fall on the precise contours of one rule tells you how central it is.
Why preterm formula is treated as a physician-directed product
A parent might reasonably ask why a doctrine built for prescription drugs applies to infant formula, which anyone can buy off a shelf. The answer lies in how these particular products are used. The specialized preterm formulas at issue — the high-calorie, nutrient-dense products used in neonatal intensive care — are ordered by physicians and administered by hospital staff as part of a baby’s medical care. They are not the standard formula a parent scoops at home.
These preterm products also occupy an unusual regulatory space. As we explain in our guide to whether preterm formula is FDA-approved, they are regulated as “exempt infant formula” and are not the subject of premarket FDA approval the way a new drug is. Because the products are selected and administered by clinicians in a hospital setting, defendants argue — and courts in the NEC litigation have largely engaged the argument — that the physician is the intermediary the warning must reach. That is why the battleground is what Abbott and Mead Johnson told neonatologists, not what any label said to parents.
Does the doctrine ever not apply?
Yes, and the exceptions matter because the NEC cases are spread across many states with different rules. Two points are worth knowing:
- State variation. Most states follow the doctrine, but not identically, and a few have limited or historically resisted it. West Virginia is the well-known example: its high court declined to adopt the doctrine in State ex rel. Johnson & Johnson v. Karl in 2007, and then the state legislature adopted it by statute (W. Va. Code § 55-7-30) in 2016. The lesson for families is that which state’s law applies can change how the warning question is framed.
- Direct-to-consumer advertising. Some courts have recognized a narrow exception where a manufacturer markets directly to patients rather than only to physicians. New Jersey’s Supreme Court recognized a version of this in Perez v. Wyeth Laboratories (1999). Whether and how any such exception fits a given product is a fact-specific, state-specific question.
None of this changes the headline point. In the ordinary NEC case, the doctrine channels the duty to warn to the physician — which is precisely why a manufacturer that failed to deliver an adequate warning to that physician can be held to answer for it.
So can you still sue the hospital or the NICU too?
Sometimes — but it is a different case with different rules. A claim against a formula maker is a product liability failure-to-warn case. A claim that the hospital or NICU staff provided substandard care — missing early NEC signs, ignoring feeding protocols, delaying treatment — is a medical malpractice case, with its own standard of care, its own expert requirements, and, in most states, much shorter filing deadlines. We cover that separate path in our overview of NEC hospital negligence.
| Claim against the formula maker | Claim against a hospital or provider |
|---|---|
| Product liability — failure to warn | Medical malpractice — substandard care |
| Duty runs to the physician (learned intermediary) | Duty runs directly to the patient |
| Consolidated in federal MDL 3026 and in state courts | Filed in the relevant state court under that state’s malpractice rules |
| Filing deadline set by product-liability limitations | Often a shorter, separate malpractice deadline and pre-suit steps |
Which of these fits a particular family is not something anyone can answer from a headline — it depends on what the chart shows. That is one more reason the complete NICU record is the honest starting point, and why deadlines are the thing to check first, since the malpractice clock can run out well before the product-liability one.
Why this makes what the company knew — and told doctors — the center of the case
If the manufacturer’s duty runs to the physician, then the evidence that matters most is what the manufacturer knew about the NEC risk and what it communicated to the medical community. That is why these cases turn heavily on the science and the corporate record: the peer-reviewed research linking cow’s-milk-based formula to NEC in preterm infants, the labeling and medical-information materials the companies provided, and the timeline of what was known when. We walk through the research in our explainer on the science linking cow’s-milk formula to NEC.
For a family, the takeaway is practical. The question is not “did our doctor make a mistake?” It is “was our doctor given the full truth about the risk?” The learned intermediary doctrine is the reason that reframing is the correct one — and the reason a family is not, in any sense, blaming the NICU nurses and physicians who cared for their child by pursuing a claim against the company.
What a Board Certified trial lawyer takes from the doctrine
“Parents come in feeling like they have to choose between being grateful to the NICU and being angry at someone, and the learned intermediary rule is the thing that dissolves that false choice,” says Alex Alvarez, Managing Partner of The Alvarez Law Firm and a Board Certified Civil Trial Lawyer. “The doctrine says the company’s duty was to warn the doctor. So when I take a case, I am not standing up to say the neonatologist failed. I am asking what the manufacturer knew and whether it gave that neonatologist the whole story. Those are two very different accusations, and only one of them is what these cases are about.”
“When I review a file, I read the feeding orders next to what the medical literature and the product information were saying at the time,” says Herb Borroto, M.D., J.D., the firm’s Medical-Legal Expert. “A physician can only act on the information in front of them. My job is to reconstruct what information that was — what the risk warnings actually conveyed, and whether they matched what was known in the science. That is the heart of a failure-to-warn case, and it is why the doctrine puts the focus on the manufacturer rather than the bedside.”
This is general information, not legal or medical advice. This article explains a legal doctrine in general terms. It does not evaluate any product, diagnose any child, or predict the outcome of any case. The law varies by state, doctrines can be applied differently on different facts, and rulings can be appealed or revisited. Past results do not guarantee future outcomes; every case is evaluated on its own facts.
How The Alvarez Law Firm approaches a NEC family’s case
When we review a potential NEC formula case, we start with the record and the science, not the headlines. We request the complete NICU chart under the HIPAA right of access, line up the feeding orders against the diagnosis and imaging, and focus on the question the law actually asks: what warning about the NEC risk reached the treating physicians, and whether it was adequate. Our team, led by Board Certified Civil Trial Lawyer Alex Alvarez and supported by Medical-Legal Expert Herb Borroto, M.D., J.D., handles that work so families can stay focused on their child.
Free, confidential case review. No fees unless we recover compensation for you.
- Understand the record: the NICU documents an NEC case is built on.
- The science the warning had to reflect: the research linking cow’s-milk formula to NEC.
- A related concept: what “warning causation” means.
- See if your family qualifies: Do I qualify for an NEC lawsuit?
Frequently asked questions
If the doctor ordered the formula, why is the NEC lawsuit against the formula company?
Because the NEC baby formula lawsuits are failure-to-warn product liability claims, and the core allegation is that the manufacturer — Abbott (Similac) or Mead Johnson (Enfamil) — did not adequately warn about the NEC risk of cow’s-milk-based formula for premature infants. Under a rule called the learned intermediary doctrine, a manufacturer of a physician-directed product generally satisfies its duty to warn by warning the treating physician, not the parent. So the legal question is whether the company gave the doctor an adequate warning. If it did not, the failure is the manufacturer’s, even though the doctor wrote the feeding order.
What is the learned intermediary doctrine?
The learned intermediary doctrine is a rule in product liability law that says a manufacturer of a prescription-type or physician-directed product ordinarily discharges its duty to warn by giving an adequate warning to the healthcare provider, who then uses professional judgment to decide what is right for the patient. The term was coined by the Eighth Circuit in Sterling Drug v. Cornish in 1966 and is reflected in Section 6(d) of the Restatement (Third) of Torts: Products Liability. Most states follow some version of it.
Does the learned intermediary doctrine mean the formula companies cannot be held responsible?
No. The doctrine defines who the manufacturer must warn; it does not give the manufacturer immunity. If a company failed to give the physician an adequate warning about the NEC risk, a failure-to-warn claim can proceed. What the doctrine adds is a second question called warning causation — whether a stronger warning to the doctor would actually have changed the feeding decision. That question is answered case by case, on the specific NICU record.
Can I still sue the hospital or the NICU doctors for my baby’s NEC?
Possibly, but that is a separate kind of claim. A claim against a formula manufacturer is a product liability failure-to-warn case; a claim against a hospital or provider for substandard neonatal care is a medical malpractice case, with its own standard of care, its own experts, and often much shorter filing deadlines. The two can sometimes exist alongside each other. Which claims fit a particular family depends on what the records show, so the honest first step is to have the complete NICU chart reviewed.
Sources
- Sterling Drug, Inc. v. Cornish, 370 F.2d 82 (8th Cir. 1966) (origin of the “learned intermediary” description of the prescribing physician).
- Restatement (Third) of Torts: Products Liability § 6(d) (1998) (manufacturer’s duty to warn prescribing and other health-care providers). American Law Institute.
- American Bar Association — “Inside the Learned Intermediary Doctrine” and “Recent Developments in the Learned Intermediary Doctrine” (overview of the rule and its state-by-state status). americanbar.org
- State ex rel. Johnson & Johnson Corp. v. Karl, 220 W. Va. 463, 647 S.E.2d 899 (2007) (West Virginia declines to adopt the doctrine); W. Va. Code § 55-7-30 (2016) (legislature later adopts it).
- Perez v. Wyeth Laboratories, Inc., 161 N.J. 1, 734 A.2d 1245 (1999) (direct-to-consumer advertising exception in New Jersey).
- Mar v. Abbott Laboratories, No. 25-2587 (7th Cir. July 24, 2026) (affirming summary judgment for Abbott on warning causation in the first federal NEC bellwether). Via the U.S. Court of Appeals for the Seventh Circuit. media.ca7.uscourts.gov
- U.S. Judicial Panel on Multidistrict Litigation — MDL No. 3026, In re: Abbott Laboratories, et al., Preterm Infant Nutrition Products Liability Litigation (N.D. Ill., Judge Rebecca Pallmeyer). jpml.uscourts.gov
- U.S. Food & Drug Administration — Exempt Infant Formula (regulation of specialized preterm formulas; 21 U.S.C. § 350a). fda.gov