Lauren Roller, PharmD, BCCCP
Residency Program Director
Lauren Roller serves as the Residency Director at AHS. She is from Indiana and received her PharmD degree at Purdue University. Lauren completed her PGY1 training at Regional One Health in Memphis, Tennessee and went on to complete her PGY2 training in critical care at the University of Colorado Denver. Lauren served as one of the Critical Care Pharmacists for the Surgery and Trauma intensive care teams for 6 years until Summer of 2022 when she transitioned to be a Substance Use Disorder Treatment Clinical Pharmacist for the Bridge Clinic team at Highland. Outside of work, Lauren enjoys traveling, exploring the Bay Area, wine tasting, watching musicals, and visiting National Parks.
Kristin Lee, PharmD, BCPS
Residency Coordinator
Kristin Lee serves as the Residency Program Coordinator at AHS. She received her PharmD from the University of Michigan College of Pharmacy and completed her PGY-1 general practice residency at Alameda Health System, Highland Hospital. Her current role involves rotating through internal medicine, emergency department, and infusion center. Kristin serves as the lead for following up on medication occurrences. She is an active member of the Golden Gate chapter of CSHP. In her free time, Kristin enjoys traveling around the world, trying out new restaurants, good reads, and being outdoors.
Diana Thamrin, PharmD, BCPS
System Director of Pharmacy
Diana Thamrin is the System Director of Pharmacy at AHS. She received her PharmD degree from University of the Pacific and completed her PGY1 training at Alameda Health System in 2005. Diana has implemented both ambulatory and acute care clinical programs at AHS and expanded learning opportunities for pharmacy residents and APPE students. Diana is responsible for the strategic alignment and integration of all pharmacy initiatives system-wide as it relates to sustainability, access, quality, and patient experience as well as further expanding the scope of practice for pharmacists at AHS. She is a preceptor for the concentrated Pharmacy Administration elective offered to students and residents and was recognized with a Distinguished Service award in 2017 by University of the Pacific for mentoring and teaching. Diana is actively involved in the Diablo Chapter of CSHP serving as a committee chair and Board member from 2015-present. In her spare time, she enjoys spending time with her daughters and husband, urban hikes in San Francisco, and trying new fitness classes.
Priya Patel, PharmD
System Medication Safety Officer, Clinical Pharmacy Manager
Priya Patel serves as the System Medication Safety Officer/ Clinical Pharmacy Manager for Alameda Health System. She received her PharmD degree from the University of the Pacific and completed her PGY1 training at Mercy Healthcare in Sacramento. Her responsibilities include oversight on Medication Safety/regulatory requirements for all campuses and implementation of strategic medication safety plans as well as provide leadership in clinical pharmacy. She serves as the co-chair of the Medication Safety Committee, and actively participates on the Patient Safety Committee and Quality Council. She serves as a preceptor for pharmacy students and residents in their Medication Safety Elective Rotation. She enjoys salsa dancing, flying on small private planes, sailing, wine tasting and cooking.
Eric Mahone, PharmD, BCACP
Clinical Pharmacy Manager – Ambulatory Care
Eric Mahone is the pharmacy manager for our primary and specialty clinics across AHS, overseeing Pharmacy-led Ambulatory Care services for refill, immunization, diabetes, hypertension, heart failure, infusion center/oncology, anticoagulation, HIV, and substance use disorders. He also serves as the primary preceptor for the Ambulatory Care II and Ambulatory elective rotations for residents at Highland. He received his PharmD from Virginia Commonwealth University in Richmond, VA in 2008. He completed a PGY-1 Residency at Martha Jefferson Hospital in Charlottesville, VA and a PGY-2 in Primary Care/Ambulatory Care at the University of Washington in Seattle, WA. He is board certified in Ambulatory Care (BCACP). In addition to his areas of practice, he is interested in teaching and healthcare communication.
Tina J. Yoo, PharmD
Clinical Pharmacy Lead – Acute Care
Tina Yoo received her PharmD degree from Loma Linda University School of Pharmacy. She completed her PGY1 General Practice Residency at St. Joseph’s Medical Center in Stockton, CA and her PGY2 Cardiology Pharmacy Residency at Western University of Health Sciences/VA Greater Los Angeles Medical Center in Los Angeles, CA. Tina is currently practicing Internal Medicine, Critical Care, Emergency Medicine and preforming Lead projects at Highland Hospital. She is a member of the Code Blue, ED OPs and P&T Committees. In her spare time, she enjoys hiking, doing art projects with her kids, gardening, watching movies and snuggling with her dog.
Jamie Encarnacion, PharmD
Inpatient Pharmacy Manager
Jamie Encarnacion received her PharmD degree from the University of the Pacific and completed her PGY1 Residency at Alameda Health System – Highland Hospital in 2016. After her residency, she worked at Highland Hospital as an on-call Clinical Pharmacist across most Acute Care specialties including Internal Medicine, ICU, and ER and went on to become one of Highland’s Night Shift Pharmacists. She then transitioned to the Inpatient Pharmacist-In-Charge/Inpatient Lead Pharmacist until October 2022, when she became the new Inpatient Operations Manager. Since 2020, she has served as the residency’s primary preceptor for the initial and longitudinal staffing rotation. In her free time, she loves traveling to different countries, trying new Michelin restaurants around the Bay Area, and watching movies and musicals.
Matthew Gutierrez, PharmD
Inpatient Pharmacy Supervisor
Matthew Gutierrez is the Inpatient Pharmacy Supervisor for Highland Hospital Pharmacy. He received his PharmD from Loma Linda University School of Pharmacy in 2014 and completed a PGY-1 from UC San Diego Health in 2015. Matt worked as a clinical pharmacist for a few years at various institutions in the Bay Area, before transitioning to pharmacy admin as a Medication Safety Officer. Matt has worked in pharmacy administration since 2017. In his current role at Highland Hospital, his responsibilities include oversight of inpatient pharmacy operational duties for acute care and ambulatory infusion. In his free time, he enjoys cooking, traveling, and spending time with his dog.
Tiffany Chui, PharmD
Inpatient Pharmacist in Charge
Tiffany Chui received her PharmD degree from Touro University and completed her PGY1 Residency at Alameda Health System – Highland Hospital. She worked for Highland Hospital as an on-call Clinical and Operational Pharmacist then transferred to Alameda Hospital to work as a full time Clinical Pharmacist. She has now returned to Highland Hospital to serve as the Inpatient Pharmacist In Charge and Lead Pharmacist. In her free time, she loves traveling, her dog, reading, and spending time with friends and family.
Natalie Fan, PharmD, BCPS
Natalie Fan is a clinical pharmacist specialist in hematology/oncology. Her current role includes managing the inpatient oncology patients and assisting with medication management for the infusion center and specialty clinics. Previously, Natalie worked in the ambulatory care clinics, the inpatient internal medicine service, and the emergency room. Natalie received her PharmD from the University of the Pacific and completed a PGY-1 General Practice Residency at Highland Hospital. She is an active member of CSHP-Diablo Chapter (DSHP) and has held several board member roles. In her free time, she enjoys watching movies, traveling, snowboarding, surfing, practicing martial arts, trying new foods, and spending time with her family.

Cindy Kang, PharmD
Cindy Kang is a clinical pharmacist specialist in the Trauma and Surgical Intensive Care Unit as well as the other surgical services at Highland Hospital. She is from Honolulu, HI and received her PharmD degree from the University of Washington. She completed her PGY-1 Pharmacy Residency at Santa Clara Valley Medical Center and PGY-2 Cardiology Pharmacy Residency at UC Davis Medical Center. During her free time, she enjoys playing golf, snowboarding, cooking, and sci-fi.
Matt Labreche, MS, PharmD, BCPS AQ-ID
Matt Labreche received his PharmD degree from Northeastern University in Boston, MA before completing a 2 year combined MS/PGY-1 pharmacy residency program at The University of Texas at Austin. While conducting research on MRSA skin and soft tissue infections for his MS degree, he realized his desire to embark on a career in infectious diseases pharmacy. Matt then completed a PGY-2 Infectious Diseases residency at The Johns Hopkins Hospital in Baltimore, MD. Following his PGY-2 training, he accepted a position with Kaiser Permanente NW in Portland, OR to help improve their antimicrobial stewardship program. Matt joined Alameda Health System in 2016 as the Infectious Diseases Pharmacist at Highland Hospital and his responsibilities include management of the antimicrobial stewardship program and quality improvement projects. He is an active member of the Society of Infectious Diseases Pharmacists (SIDP), American College of Clinical Pharmacy (ACCP), and Infectious Diseases Society of America (IDSA). In his spare time he enjoys traveling, snowboarding, and outdoor activities.
Joseph Lam, PharmD
Joseph Lam is a Clinical Pharmacy Specialist in Critical Care unit. Currently, he participates in daily rounding with the Medical ICU team. He is the critical care pharmacist, providing services of monitoring for drug-related side effects, dosage adjustment, therapeutic drug monitoring, parenteral nutrition monitoring and others. He is also a member of the IRB (Investigational Review Board), Critical Care committee, Sepsis Harm Reduction committee, and Food and Nutrition committee. He also serves as the preceptor for the medical critical care rotations at Highland. He received his Doctorate of Pharmacy from University of California, San Francisco in 1999. He is an active member of the Society of Critical Care Medicine (SCCM). In his spare time, he enjoys exercise, swimming, photography, listening to music and watching movies.
Derex Louie, PharmD, BCPS
Derex Louie received his BS from UC Berkeley and his PharmD at Creighton University in Omaha, Nebraska. He completed his PGY-1 Residency at Highland Hospital. Derex practices clinical pharmacy in Acute Care/Internal medicine/Emergency Medicine. He serves as one of the primary preceptors for the Internal Medicine and Emergency Medicine rotations. Derex has been a member for the Pharmacy and Therapeutics Committee and continues to contribute to drug policy implementation practice at AHS. His professional interests include drug information, improving medication use practices, and nursing education.
Alice Peng, PharmD, BCPS
Alice Peng received her PharmD degree from the University of the Pacific and completed her PGY1 at Kern Medical in Bakersfield, CA. She currently serves as one of the clinical pharmacists for internal medicine, critical care, and emergency medicine. Outside of work, Alice enjoys traveling, snowboarding, playing board games, and reading.
Jennifer Pham, PharmD
Jennifer Pham received her PharmD from University of the Pacific and completed her PGY1 Residency at Alameda Health System – Highland Hospital. She currently serves as one of the clinical pharmacists for Internal Medicine, Critical Care, and Emergency Medicine. In her free time, she loves working out, hanging out, and baking/cooking/eating.
Vivian Phan, PharmD, BCACP, AAHIVP
Vivian Phan serves as the ambulatory care clinical pharmacist specialist in hematology/oncology. She received her PharmD from MCPHS University, Boston and completed an ambulatory care PGY1 residency with a focus in HIV/AIDS at UC Davis Health. In her position at Highland Hospital, she manages infusion center orders for oncology as well as various other specialty clinics. She works collaboratively with oncologists and nursing staff to provide patient education and supportive therapy management. In her free time, Vivian enjoys traveling abroad, baking, watching movies, and spending time with family and friends.
Yolanda Ramos, PharmD, BCPS, AAHIVP
Yolanda is a Clinical Pharmacist Specialist in Ambulatory Care. Currently, she practices in the Adult Immunology Clinic (AIC), providing Primary Care and Specialty Pharmacy Services to patients living with HIV. Patients are referred for adherence counseling, smoking cessation and chronic disease management to improve patient outcomes. Previously, she was the Transitional Care Pharmacist working with high risk and homeless populations to reduce readmission rates at Highland Hospital. She received her PharmD Degree from the University of California, San Diego Skaggs School of Pharmacy and completed her PGY1 Residency at Alameda Health System, Oakland, CA. She is an active member of CSHP- Diablo chapter and serves many roles on the board. Other areas of interest include providing end of life care to patients. In her spare me she enjoys exploring Oakland and trying new foods.
Alvin Tong, PharmD
Alvin Tong received his PharmD from Touro University, California and completed his PGY1 Residency at Alameda Health System – Highland Hospital, Oakland. He is an Ambulatory Care Clinical Pharmacist Specialist with focus in the cardiology and gastrointestinal specialty clinics, additionally he is cross trained for the hematology/oncology service. Alvin is an active member of the Diablo Chapter of CSHP and precepts pharmacy students for their ambulatory care rotations. In his free time, he enjoys a variety of outdoor activities, dog-sitting other people’s dogs, and the internet.
Jennifer Toy, PharmD, BCACP
Jennifer Toy earned her PharmD from the University of California, San Francisco (UCSF). She completed a PGY1 at the Veterans Affairs Puget Sound in Seattle and went on to complete specialized PGY2 training in ambulatory/primary care at the University of Washington. She worked for UCSF in the Central Valley establishing pharmacist services in rural ambulatory care clinics before coming to the Highland Adult Medicine Clinic in 2017. At Highland, she is passionate about serving high-risk diabetic patients in the Chronic Care Clinic and enjoys precepting pharmacy learners for their ambulatory care rotations. She is on a side quest to run every street on Alameda Island.
Sarah Vuilleumier, PharmD, BCPP
Sarah Vuilleumier specializes in psychiatric pharmacy and provides clinical services for AHS’s inpatient psychiatric hospital, John George Psychiatric Pavilion, and Fairmont Hospital Skilled Nursing Facility, as well as serving as Pharmacist in Charge for John George. She is involved in several committees and works to improve medication use practices at both locations. Sarah received her PharmD from the University of California, San Francisco. She completed a health policy residency with California Health and Human Services and a PGY2 in psychiatry with UCSF/San Francisco County. Outside of work she enjoys mountain biking, traveling and adventuring with her dog.