## Facts

- Wilma Peggy Carlin alleged she suffered personal injuries after ingesting Halcion, a prescription sleep medication manufactured by The Upjohn Company.
- Carlin claimed Upjohn failed to warn about dangerous side effects that were known or reasonably scientifically knowable when the drug was distributed.
- She asserted causes of action including strict products liability for failure to warn and breach of express and implied warranty based on inadequate warnings.
- Upjohn demurred, arguing that California law bars strict liability claims against prescription drug manufacturers and urged limiting warning claims to negligence.
- The trial court sustained the demurrer.
- The Court of Appeal issued a writ directing the trial court to vacate its ruling and overrule the demurrer.
- The California Supreme Court granted review to determine whether strict liability and warranty warning-based theories are available in the prescription-drug context.

## Issues

1. Whether a plaintiff injured by a prescription drug may plead strict products liability and breach of warranty based on failure to warn of risks that were known or reasonably scientifically knowable at the time of distribution.
2. Whether prior precedent barring strict liability design-defect claims for prescription drugs also bars, or reduces to negligence, strict liability failure-to-warn claims against prescription drug manufacturers.

## Decision

- The California Supreme Court affirmed the Court of Appeal’s directive to overrule Upjohn’s demurrer.
- The court held that a prescription drug manufacturer may be held strictly liable for failure to warn of risks that were known or reasonably scientifically knowable when the drug was distributed.
- The court held that precedent shielding prescription drug manufacturers from strict liability design-defect claims does not eliminate strict liability failure-to-warn claims.
- The court held that Carlin adequately stated breach of express and implied warranty claims premised on inadequate warnings.
- The superior court was directed to vacate the order sustaining the demurrer and to overrule it as to the strict liability and warranty causes of action.

## Legal Principles

- In strict liability failure-to-warn cases, the duty to warn is measured by dangers that were known or reasonably scientifically knowable at the time of distribution.
- A manufacturer can be liable if a risk was not actually known but was reasonably discoverable through accessible scientific knowledge at the relevant time.
- Prescription drug manufacturers are not strictly liable on a design-defect theory for properly prepared drugs with proper warnings, but they remain subject to strict liability for inadequate warnings concerning known or reasonably knowable risks.
- Strict liability failure-to-warn doctrine applies to all manufacturers, including prescription drug manufacturers.
- Inadequate warnings may support breach of implied warranty (lack of fitness for ordinary purposes) and breach of express warranty (inconsistent with the manufacturer’s representations about safety or risks).

## Conclusion

The court held that patients alleging injury from a prescription drug may proceed on strict liability and warranty theories based on inadequate warnings when the alleged risk was known or reasonably scientifically knowable at the time the drug was distributed, and it required the trial court to overrule the manufacturer’s demurrer to those claims.


Carlin v. Superior Court, 13 Cal. 4th 1104 (Cal. 1996)