NLM Systems Unavailable During Planned Maintenance beginning Friday, July 25, 2025

On Friday, July 25, 2025, beginning at 9:00 p.m. EDT, the National Library of Medicine (NLM) will perform planned maintenance on its data center infrastructure. This upgrade is part of an ongoing effort to enhance the long-term reliability and stability of NLM-hosted services.

The maintenance window is expected to last 24 hours or longer. During this time, users may experience interrupted access or degraded performance across a range of NLM resources, including databases, APIs, search tools, submission systems, and programmatic services.

All systems are expected to be fully restored by Monday, July 28, 2025.

We apologize for any inconvenience this temporary disruption may cause and appreciate your understanding as we work to improve our infrastructure.