Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.

Leonard John Preuss

Individual provider Addiction (Substance Use Disorder) Counselor · NPI 1700172541

Leonard John Preuss is an Addiction (Substance Use Disorder) Counselor in El Cajon, California. Practices as a sole proprietor. Registered with an NPI since 2011.

In the registry since
2011

Practice location Address checks out

1400 N Johnson Ave Ste 101
El Cajon, CA 92020-1650
Phone: (619) 442-0277
Show map & directions

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Addiction (Substance Use Disorder) Counselor (primary) Taxonomy 101YA0400X

Record details

NPI number1700172541
Entity typeIndividual (Type 1)
GenderMale
Sole proprietorYes
NPI enumeratedJune 20, 2011
Last updated in NPPESJune 20, 2011

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