Gemma G Guillermo, MD
Psychiatry · San Jose
- Medicare standing
- Clear
- Enrolled, allowed to bill and order, not excluded
- Plans that list them
- Not verified
- Not the same as out of network.
- Office
- 1
Offices
1 location · County of Santa Clara · 1,000 clinicians in this group
Plan participation
Not verified
We could not verify current plan participation for this doctor. This does not mean they are out of network. Call Dr. Guillermo’s office at (408) 885-5000 to ask if they take your plan before you enroll.
California Medical Board record
Licence A61066 · Current
Licensed to practise in California · since 1996 · expires 2028-07-31 · Cornell University Medical College.
Matched on the licence number without its letter prefix; check the name before relying on it.
No disciplinary actions, convictions, malpractice judgments or citations in this record.
Original Medicare doctor bills
$15,595
Medicare paid this office $15,595 for 38 people.
This is what Medicare paid the clinician — not Medicare Advantage, and not the pharmacy.
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 28 | $4,804 | $60 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 23 | $3,281 | $143 |
| Subsequent hospital care with straightforward or low level of medical decision making, per day at least 25 minutes | 19 | $2,983 | $40 |
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 14 | $2,235 | $97 |
| Hospital discharge day management, more than 30 minutes | 19 | $1,915 | $96 |
Who their Medicare patients are
38 Original Medicare patients in 2024. Average age 49 · Women 34% · Also on Medicaid 100% · Health risk score 1.25. At or below the middle of the specialty; the typical psychiatry clinician is at 1.35.
Conditions among them: High blood pressure 63% · Diabetes 47% · Depression 29%.
The office billed $213,280, Medicare allowed $21,902 and paid $15,595; for 223 services of 7 kinds.
Original Medicare patients only. A risk score of 1.0 is the average Medicare patient; higher means sicker. Any count under 11 is hidden.
Year by year
| 2024 | 38 | 223 | 49 | 1.25 | $213,280 | $15,595 |
| 2023 | 38 | 202 | 50 | 1.35 | $200,487 | $16,083 |
| 2022 | 24 | 170 | 54 | 1.31 | $158,215 | $14,994 |
| 2021 | 27 | 183 | 55 | 1.71 | $171,850 | $19,883 |
| 2020 | 27 | 136 | 53 | 1.39 | $130,872 | $13,708 |
| 2019 | 44 | 253 | 52 | 1.10 | $192,278 | $21,756 |
| 2018 | 44 | 286 | 53 | 1.05 | $186,185 | $27,195 |
| 2016 | 36 | 238 | 50 | 1.55 | $36,047 | $9,959 |
Original Medicare only. A service billed for fewer than 11 people in a year is hidden, so the lines can add up to less than the year's total.
See the services billed each year
2023: 5 services
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 26 | $5,894 | $70 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 19 | $3,154 | $150 |
| Subsequent hospital care with straightforward or low level of medical decision making, per day at least 25 minutes | 14 | $2,439 | $44 |
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 11 | $2,413 | $110 |
| Hospital discharge day management, more than 30 minutes | 17 | $1,874 | $110 |
2022: 4 services
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 21 | $8,179 | $72 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 14 | $2,462 | $154 |
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 14 | $2,036 | $102 |
| Hospital discharge day management, more than 30 minutes | 15 | $1,759 | $110 |
2021: 4 services
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 18 | $8,422 | $114 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 17 | $6,373 | $80 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 13 | $3,283 | $219 |
| Hospital discharge day management, more than 30 minutes | 11 | $1,325 | $120 |
2020: 4 services
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 17 | $5,435 | $77 |
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 17 | $3,652 | $107 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 11 | $2,725 | $195 |
| Hospital discharge day management, more than 30 minutes | 12 | $1,385 | $107 |
2019: 4 services
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 32 | $8,471 | $92 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 28 | $6,262 | $62 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 22 | $3,536 | $147 |
| Hospital discharge day management, more than 30 minutes | 29 | $3,040 | $95 |
2018: 4 services
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 34 | $12,639 | $92 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 34 | $5,702 | $154 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 26 | $4,461 | $65 |
| Hospital discharge day management, more than 30 minutes | 30 | $3,456 | $99 |
2016: 1 service
| Subsequent hospital care with straightforward or low level of medical decision making, per day at least 25 minutes | 29 | $7,135 | $34 |
Drugs they prescribed that Part D paid
$31,131
Pharmacies billed $31,131 in 2024.
This is pharmacy cost, not the office bill, and not what patients paid.
Opioids were 0% of their Part D prescriptions (0 of 98) in 2024. At or below the middle of the specialty; the typical psychiatry clinician is at 0%.
84 generic and 14 brand-name prescriptions · $31,131 in drug cost.
Part D prescriptions only. The opioid rate is opioid prescriptions as a share of all this clinician's Part D prescriptions; surgeons and pain specialists run higher than others, so it is shown against the same specialty.
| Hydroxyzine | 14 | $45 | $3 |
Year by year
| 2024 | 98 | 23 | 0% (0) | 14% | $31,131 |
| 2023 | 90 | 24 | 0% (0) | 13% | $21,984 |
| 2022 | 73 | 23 | 0% (0) | None | $3,798 |
| 2021 | 61 | 21 | 0% (0) | None | $6,225 |
| 2020 | 88 | 21 | 0% (0) | None | $3,066 |
| 2019 | 124 | 35 | 0% (0) | 14% | $4,909 |
| 2018 | 120 | 38 | 0% (0) | None | $4,865 |
| 2017 | 53 | 23 | 0% (0) | None | $1,484 |
| 2016 | 26 | None | 0% (0) | None | $2,190 |
| 2015 | 34 | 21 | 0% (0) | None | $2,064 |
| 2014 | 34 | 20 | 0% (0) | None | $691 |
| 2013 | 32 | 16 | 0% (0) | None | $1,244 |
Part D prescriptions only. A drug prescribed to fewer than 11 people in a year is hidden.
See the drugs prescribed each year
2019: 1 drug
| Divalproex | 14 | $159 | $11 |
Money from drug and device companies
$139 in 2025
| 2025 | 1 | 1 | None | $139 |
| 2024 | 2 | 4 | None | $476 |
| 2023 | 2 | 3 | None | $364 |
Paid work is consulting, speaking, honoraria and royalties, as opposed to meals and travel.
A payment is not proof that care is biased.
| Neurocrine BioSciences | Ingrezza | $139 | 1 payment
|
See the published payment
| Neurocrine BioSciences | Meals · 2025-09-16 | Ingrezza | $139 |
See earlier years (2024, 2023)
2024: $476
| Teva Pharmaceuticals USA | Uzedy | $239 | 2 payments
|
| Alkermes | Lybalvi | $237 | 2 payments
|
2023: $364
| Alkermes | Aristada | $214 | 2 payments
|
| Janssen Pharmaceuticals | Invega Sustenna | $150 | 1 payment
|
Checkups this office reported
Medicare did not publish checkup rates for this clinician.
- Medicare’s overall office score
- 80.6 / 100
- Scores the office’s reporting and systems. It is not a grade for how the doctor treats you.
Professional record
- NPI
- 1831154418
- Licence
- CA 61066California A61066: Current · expires 2028-07-31
- Trained
- Js Weill Medical College, Cornell University, 1995
- Gender
- Female
More record details
- Sole proprietor
- Yes
- Medicaid ID
- CA 3967836
- Taxonomy
- Psychiatry (2084P0800X)
- Mailing address
- 2290 Vera Ave, Redwood City, CA, 94061
- NPI first listed
- 2006-04-18
- NPI last updated
- 2019-02-13
This is when the NPI record was last certified, not a medical board exam.