240-773-0300 | info@mercyhealthclinic.org

Mon & Wed: 8:30 am–5 pm
Tues &Thurs: 8:30 am–8 pm
Fri: Closed

Mercy Health Clinic is a volunteer-based, safety-net medical center staffed by licensed medical professionals that include internal medicine and family practice physicians, nurse practitioners, physician assistants, behavioral health counselors, and many specialty physicians. In addition to a small paid staff, our 100+ volunteers also provide translation, administrative and other services. To learn more about career and volunteer opportunities see

Clinic Staff


Mark Foraker – President and CEO
MaryAnn Bishop, MD – Medical Director
Laureen Harkins, ANP – Clinical Director
Maria Maravilla – Clinic Manager

Development and Communications

Denise Fredericks, Director
Joan Ronnenberg, Consultant


Glenda Aviles – Medical Assistant

Margaret Camarca – Pharmacy Nurse

Hau Che – Registered Nurse

Glenovan Brown-Sealey – Nurse Practitioner
Wendy Gotlewski – Pharmacist

Sonia Louis LaPierre – Nurse Practitioner

Jasmin Martinez – Referral Coordinator

Manuel Hernandez – Medical Assistant

Jenny Moncada – Patient Scheduler

Lorraine Ponce – Medical Assistant

Nancy Ponce – Receptionist

Gabriela Risueno – Medical Assistant

Annette Ruah – Volunteer Coordinator

Diana Seitelman – Physician Assistant

Shu-Yen Tsai – Pharmacy Technician

Sinia Veliz – Medical Assistant

David Want – Nurse Practitioner