DR. KAREN CHEE M.D.
Prescription History 1487637310
Internal Medicine - Hematology & Oncology in San Mateo, CA
What does Dr. Chee prescribe?
In 2024, Dr. Chee wrote 633 Medicare prescriptions for 21 medications. The most prescribed was Eliquis (apixaban), with 69 prescriptions.
Medicare Part D only. These are prescriptions filled by people with Medicare drug coverage in 2024, from the CMS data released in 2026, the most recent year available. CMS does not publish medications with fewer than 11 prescriptions, so this is not a full list of what Dr. Chee prescribes.
Medications 21 medications
Prescriptions filled under Medicare Part D in 2024. Select a medication to see what it is used for and how it compares with other California prescribers.
What it is used for
Apixaban is used to prevent serious blood clots from forming due to a certain irregular heartbeat (atrial fibrillation) or after hip/knee replacement surgery.
Compared with California prescribers
Dr. Chee wrote 69 prescriptions for Eliquis, about as often as the typical California prescriber of it (73). Medicare paid $729.43 per fill, versus $923.33 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
Acyclovir is used to treat infections caused by certain types of viruses.
Compared with California prescribers
Dr. Chee wrote 64 prescriptions for Acyclovir, about 2.5 times as often as the typical California prescriber of it (25). Medicare paid $14.25 per fill, versus $18.27 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
This medication is used to treat certain cancers (mantle cell lymphoma, marginal zone lymphoma, Waldenstrom's macroglobulinemia, chronic lymphocytic leukemia, small lymphocytic lymphoma, follicular lymphoma).
Compared with California prescribers
Dr. Chee wrote 58 prescriptions for Brukinsa, about 1.9 times as often as the typical California prescriber of it (30). Medicare paid $13,717.74 per fill, versus $12,543.75 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
This medication is used alone or with other medications to prevent nausea and vomiting caused by cancer drug treatment (chemotherapy) and radiation therapy.
Compared with California prescribers
Dr. Chee wrote 56 prescriptions for Ondansetron Hcl, about 2 times as often as the typical California prescriber of it (28). Medicare paid $14.03 per fill, versus $14.67 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
This medication is used to treat severe nausea and vomiting from certain causes (for example, after surgery or cancer treatment).
Compared with California prescribers
Dr. Chee wrote 45 prescriptions for Prochlorperazine Maleate, about 1.5 times as often as the typical California prescriber of it (29). Medicare paid $16.22 per fill, versus $13.81 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
This medication is a combination of two antibiotics: sulfamethoxazole and trimethoprim.
Compared with California prescribers
Dr. Chee wrote 45 prescriptions for Sulfamethoxazole-Trimethoprim, about 1.8 times as often as the typical California prescriber of it (25). Medicare paid $5.99 per fill, versus $4.62 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
This medication is used to treat certain bone marrow disorders (myelofibrosis, polycythemia vera).
Compared with California prescribers
Dr. Chee wrote 38 prescriptions for Jakafi, about 1.3 times as often as the typical California prescriber of it (28). Medicare paid $13,657.46 per fill, versus $15,437.07 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
This medication is used by people with sickle cell anemia to reduce the number of painful crises caused by the disease and to reduce the need for blood transfusions.
Compared with California prescribers
Dr. Chee wrote 37 prescriptions for Hydroxyurea, about as often as the typical California prescriber of it (35). Medicare paid $28.82 per fill, versus $28.53 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
Rivaroxaban is used to prevent blood clots from forming due to a certain irregular heartbeat (atrial fibrillation) or after hip or knee replacement surgery.
Compared with California prescribers
Dr. Chee wrote 34 prescriptions for Xarelto, about 80% as often as the typical California prescriber of it (43). Medicare paid $902.34 per fill, versus $952.66 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
This medication is used to treat certain cancers (such as chronic lymphocytic leukemia/small lymphocytic lymphoma, Waldenstrom's macroglobulinemia).
Compared with California prescribers
Dr. Chee wrote 21 prescriptions for Imbruvica, about 85% as often as the typical California prescriber of it (25). Medicare paid $18,013.05 per fill, versus $15,720.46 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
This medication contains 2 amide-type local anesthetics, lidocaine and prilocaine.
Compared with California prescribers
Dr. Chee wrote 21 prescriptions for Lidocaine-Prilocaine, about 85% as often as the typical California prescriber of it (25). Medicare paid $12.76 per fill, versus $20.14 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
This medication is used to treat ongoing high levels of iron in the body caused by multiple blood transfusions.
Compared with California prescribers
Dr. Chee wrote 19 prescriptions for Deferasirox, about as often as the typical California prescriber of it (19). Medicare paid $155.82 per fill, versus $1,562.97 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
This medication is used to treat diarrhea.
Compared with California prescribers
Dr. Chee wrote 19 prescriptions for Diphenoxylate-Atropine, about 90% as often as the typical California prescriber of it (21). Medicare paid $44.94 per fill, versus $17.06 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
This medication is used to treat certain types of cancer (such as acute lymphoblastic leukemia, chronic myeloid leukemia, gastrointestinal stromal tumors, and myelodysplastic/myeloproliferative diseases).
Compared with California prescribers
Dr. Chee wrote 18 prescriptions for Imatinib Mesylate, about 82% as often as the typical California prescriber of it (22). Medicare paid $3,301.69 per fill, versus $905.12 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
Tamoxifen is used to treat breast cancer.
Compared with California prescribers
Dr. Chee wrote 16 prescriptions for Tamoxifen Citrate, about half as often as the typical California prescriber of it (35). Medicare paid $36.50 per fill, versus $24.93 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
Anastrozole is used to treat breast cancer in women after menopause.
Compared with California prescribers
Dr. Chee wrote 14 prescriptions for Anastrozole, about 21% as often as the typical California prescriber of it (68). Medicare paid $16.41 per fill, versus $20.79 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
Dexamethasone is used to treat conditions such as arthritis, blood/hormone disorders, allergic reactions, skin diseases, eye problems, breathing problems, bowel disorders, cancer, and immune system disorders.
Compared with California prescribers
Dr. Chee wrote 12 prescriptions for Dexamethasone, about 34% as often as the typical California prescriber of it (35). Medicare paid $13.75 per fill, versus $13.93 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
See also Warning section.
Compared with California prescribers
Dr. Chee wrote 12 prescriptions for Loperamide, about half as often as the typical California prescriber of it (23). Medicare paid $7.32 per fill, versus $15.35 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
Lorlatinib is used to treat a certain type of lung cancer.
Compared with California prescribers
Dr. Chee wrote 12 prescriptions for Lorbrena, about 79% as often as the typical California prescriber of it (15). Medicare paid $19,095.36 per fill, versus $20,155.69 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
Prednisone is used to treat conditions such as arthritis, blood disorders, breathing problems, severe allergies, skin diseases, cancer, eye problems, and immune system disorders.
Compared with California prescribers
Dr. Chee wrote 12 prescriptions for Prednisone, about 30% as often as the typical California prescriber of it (40). Medicare paid $5.07 per fill, versus $5.64 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
What it is used for
Palbociclib is used to treat a certain type of breast cancer.
Compared with California prescribers
Dr. Chee wrote 11 prescriptions for Ibrance, about 40% as often as the typical California prescriber of it (28). Medicare paid $15,725.86 per fill, versus $15,322.98 statewide.
Volume reflects how many Medicare patients a practice sees as well as prescribing habits. It is not a measure of quality.
Questions about Dr. Chee’s prescriptions
What does Dr. Chee prescribe most?
In 2024 Medicare Part D data, Dr. Chee's most prescribed medications were Eliquis (69), Acyclovir (64) and Brukinsa (58).
How does Dr. Chee's prescribing compare with other California prescribers?
Of the 21 medications with a state comparison, Dr. Chee prescribes 6 more often than the typical California prescriber, 9 about as often and 6 less often. Volume reflects practice size as well as prescribing habits.
Does this list show every medication Dr. Chee prescribes?
No. It covers prescriptions filled by people with Medicare Part D drug coverage in 2024, and CMS leaves out any medication with fewer than 11 prescriptions.
About this data
This page shows one provider’s slice of public Medicare files. NPI Profile does not receive prescriptions or patient records.
| Source | What it provides here | Data year |
|---|---|---|
| CMS Medicare Part D Prescribers by Provider and Drug | Each medication, prescriptions, patients, 30-day fills, days of medication and cost. State comparisons average the California prescribers of the same medication and form, where at least five wrote it. | 2024 (released 2026, the most recent available) |
| CMS Medicare Part D Drug Spending Dashboard | What each medication is used for. | 2024 |
- Only prescriptions filled by people with Medicare Part D drug coverage are counted. Private insurance, Medicaid and cash purchases are not.
- CMS leaves out medications with fewer than 11 prescriptions and hides patient counts under 11.
- Cost per fill is what the plan and the patient paid the pharmacy together, not what you pay at the counter.
- Medication descriptions are summaries from CMS. They are not medical advice; ask a health care professional about any medication.
