Live
Read more

Clinic Type

Internal Medicine

Address

1605 Douglas Street, Sioux City, IA 51105; 2720 Stone Park Boulevard, Sioux City, IA 51104; Singing Hills location: UnityPoint Clinic Family Medicine - Singing Hills, 3520 Singing Hills Boulevard, Sioux City, IA 51106

Phone

712-234-1005; 712-279-3500; 712-294-7400

Email

UPH_CentralIAPrivacyOfficer@unitypoint.org

Opening Hours

Not published — contact the clinic to confirm hours.

Services Offered

Team

  • Mark O. Carlson — MD
  • Matthew Nwaneri, Hematology Oncology, Internal Medicine — MD
  • Mark S Carlson — DO
  • Dale R Holdiman — MD
  • David H. Daniels — MD

Insurance & Payment

Languages Spoken

Photos

What Patients Say

Overall sentiment across review platforms: mixed

  • WebMD (Dr. Steven Joyce): 4.5/5 (23 ratings)
  • Vitals (Dr. Kevin Preston): 2.1/5 (46 ratings)
  • Vitals (Dr. Liem Oei): 4.9/5 (14 ratings)

Patients praise

  • Doctors described as thorough, professional, and invested in long-term patient relationships
  • High-quality care for chronic or complex conditions when patients are able to access it
  • Some patients report highly personalized, attentive care and effective preventive health programs

Common complaints

  • Long wait times and slow service at clinics and hospitals
  • Reports of rude, dismissive, or unprofessional conduct by front-desk and clinical staff
  • Difficulties with communication, including unanswered calls and challenges retrieving medical records
  • Issues with billing, insurance coverage, and prescription refill processes

"We have been patients of Dr. Carlson and the staff at Siouxland Adult Medicine for several years. The care we have received over this time has been extraordinary."

Siouxland Adult Medicine Patient Review

"we sat in the lobby for 40 minutes before we even went into a room. that place is ridiculously slow... no one seems to know what they’re doing there."

MercyOne Singing Hills Family Medicine Review

"The nurse practitioner came in and diminished all of my symptoms... I should not have to spend $40 in copays just to be looked at for two minutes tops."

Family Healthcare of Siouxland - Northside Clinic Review

Synthesized from public review platforms as of Jul 11, 2026 — sources: [1][2][3][4].

Information sourced from the clinic's website as of July 11, 2026.

More internal medicine clinics in Sioux City

Sioux City, IA·Internal Medicine

Verified
Sioux City, IA·Internal Medicine

VerifiedOnline bookingEmergency care

See all internal medicine clinics in Sioux City

Comparing your options?

See other internal medicine clinics in Sioux City, or search the full directory by insurance, ratings, and more.

More Internal Medicine Clinics