Larry K. Houck Director 202-737-9629
Larry K. Houck


Larry K. Houck provides counsel on regulatory and enforcement actions by the Drug Enforcement Administration (“DEA”). His career encompasses over 35 years of conducting inspections, investigations and negotiating on behalf of both the government and industry. Mr. Houck focuses on controlled substances, prescription drugs, and regulated chemicals, helping clients navigate federal and state licensing, registration, and compliance issues.  His focus is also on marijuana/cannabis regulation, including cannabidiol (“CBD”) and hemp.

Mr. Houck counsels clients throughout the registrant supply chain on administrative, civil, and criminal proceedings. In situations where clients face enforcement action, Mr. Houck has extensive understanding of DEA’s approach and priorities. He advises pharmaceutical and chemical companies, including manufacturers, distributors, pharmacies, and health care facilities, on DEA inspections and accountability audits. By working with clients to review their business policies and practices, he helps create the infrastructure to ensure compliant reporting, record keeping, and security.

Before joining Hyman, Phelps & McNamara in 2001, Mr. Houck served as a DEA diversion investigator and policy staff coordinator. As a diversion investigator in the Washington, D.C. and Portland, Oregon, field offices, Mr. Houck conducted a full range of regulatory and criminal investigations and inspections of controlled substance and chemical registrants. While serving as a staff coordinator for the DEA’s Office of Diversion Control’s Liaison and Policy, he advised government officials and pharmaceutical and health care professionals on the Controlled Substance Act (“CSA”) and its regulations. Mr. Houck drafted and helped implement DEA’s controlled substance regulations on diversion control issues that included pain management.

Education & Admissions


J.D., Lewis & Clark Northwestern School of Law
M.A., History, George Mason University
B.A., History and European Studies, George Mason University


District of Columbia


  • Advises clients on DEA regulations, policies and practices, and other federal and state criminal and civil statutes and regulations related to controlled substances and regulated chemicals.
  • Provides counsel on DEA enforcement actions and registration issues.
  • Negotiates and prepares MOAs, MOUs, registration restrictions, show cause hearings and proceedings, Letters of Admonition, and civil demand letters.
  • Evaluates prescription drug business practices to ensure procedures that comply with regulations.
  • Advises on the regulation of chemicals, including precursor ingredients used in the manufacture of controlled substances.
  • Provides guidance on business procedures around DEA registration, record keeping and reporting, and security.

Honors & Awards

2018 President’s Award, National Association of State Controlled Substances Authorities

Speaking Engagements

  • Panelist, FDLI Webinar, High Time for a Change: Implications of DEA’s proposed Marijuana Rescheduling, June 12, 2024
  • Panelist, FDLI Legal and Practical Issues in Cannabis Regulation, Marijuana Rescheduling: Exploring FDA’s Recommendation, Stakeholder Impact, and Broader Implications, April 4-5, 2024
  • Panel Member, Webinar: HHS’ Cannabis Rescheduling Recommendation: A Long Strange Trip with Potholes, NASCSA, January 9, 2024
  • Speaker, HPM Webinar: Recent Hospital Controlled Substance Diversion Cases — Cautionary Tales, October 3, 2023
  • 2023 Opioid Abuse Management Summit, Developing an Effective and Comprehensive Opioid Management System Across the Health System, July 20-21,2023
  • Speaker, HPM Webinar: Demystifying DEA Inspections: Accountability Audits, Mirror Reviews and Mock Inspections, May 24, 2023
  • American Pharmacists Annual Meeting, Prescribing Red Flags, Corresponding Responsibility and DEA Inspections: What’s a Pharmacist To Do, March 24-27, 2023
  • Co-Presenter, HPM and Analysis Group Webinar:  Controlled Substances Act Issues: Legal Perspectives and Analytical Trends, ‘Suspicious Order’ Monitoring: The SUPPORT Act, Proposed SOM Rule, the “ORUSC,” and Distribution Trends, April 27, 2021
  • FDLI Legal and Practical Issues in the Evolving World of Cannabis Regulation Conference, Comments on DEA’s Interim Final Rule on Implementation of the Agriculture Improvement Act of 2018, December 8, 2020
  • FDLI Legal and Practical Issues in the Evolving World of Cannabis Regulation Conference, What is the Current Federal Oversight of Cannabis-Derived Products, November 18-19, 2019
  • FDLI Annual Conference: Exploring Advanced Topics in Food and Drug Law, Understanding DEA Regulations and FDA Interactions: A Case Study on Opioids, May 2-3, 2019
  • FDLI Webinar, DEA Law for the Food and Drug Community, May 30, 2018
  • National Association of Drug Diversion Investigators – Healthcare Facility RX Diversion Summit, DEA Inspections at Hospitals and Health Facilities, April 24-25, 2018
  • California Pharmacists Association Western Pharmacy Exchange, Controlled Substances: Legislative and Regulatory Update, April 12-15, 2018
  • California Pharmacists Association Western Pharmacy Exchange, Death, Taxes and DEA Inspections: Dealing with the Inevitable, February 23-26, 2017

J.D., Lewis & Clark Northwestern School of Law
M.A., History, George Mason University
B.A., History and European Studies, George Mason University


District of Columbia

Practice Areas
FDA Regulatory Categories