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Search › Illinois › 204D00000X

Allan Olthoff, D.O

NPI 1780731067 · on the registry since 2007 · sole proprietor

Practice

Address
2600 S Michigan Ave Ste 210
Chicago, IL 60616
Phone
(312) 623-3007
Fax
(312) 877-5643
Organisation at this address
Hair Haven
Medico Pllc
Alton Wong Md, Sc
Answers 2 Hairloss
Sami Atassi Md Ltd
Inferred from a shared address, not stated in the registry.
Clinicians at this address
59

Registry record

Primary taxonomy
204D00000X
204D00000X
Also registered as
207Q00000X
Licence states on file
IL
From the registry's licence fields, which are often incomplete.
Sex
Male
Record last updated
2025-07-30

Source: CMS National Plan and Provider Enumeration System. Registration is not the same as practising, and the registry records no retirement — some people listed here no longer practise. More in Illinois