How should plans respond to a drug going on shortage?

Plan response depends on the drug's volume, indication, and substitute availability. Three common response patterns:

1. High-priority (multi-million-claim drugs). Immediate action: tier alternative-product NDCs, suspend quantity limits on the affected molecule, monitor fill data weekly, communicate with prescribers about supply availability. Albuterol is the current canonical example — affecting 32M Part D claims annually.

2. PA carveout (therapeutic alternatives exist). Authorize coverage of clinically appropriate substitutes without requiring re-justification through prior authorization. For meperidine in shortage, fentanyl and hydromorphone are common substitutes; a PA carveout removes administrative friction for prescribers switching during the shortage window.

3. Source check (drug available but limited). Verify which manufacturers and NDCs are actively shipping before authorizing fills. Methylphenidate shortages often have one or two manufacturers actively distributing while others are paused; the PBM can steer fills toward shipping NDCs.

For low-volume drugs, the response is usually a simple substitute pathway. For high-volume drugs, formal P&T review may be triggered to adopt a new preferred alternative. CMS Part B-covered drugs (mostly inpatient injectables) have separate response mechanisms.

The biggest plan-sponsor mistake is treating all shortages identically. Member-disruption modeling should be proportional to claim volume.