Essam Mostafa, MD
Nephrology · Fountain Valley, CANPI 1316932270
Payments from drug & device makers
What this record shows
Almost everything reported here is food and beverage — 96.6% of the total across 19 separate payments, which is the pattern of a clinician who attends manufacturer presentations rather than one with a consulting arrangement. Boehringer Ingelheim accounts for 88.7% of it on its own, with 2 other manufacturers making up the rest. Reporting peaked in 2024 at $294 and has fallen 80.5% since, to $57 in 2025. That places this record below the midpoint for nephrology clinicians in CA, where the typical reported total is $1,018.
Across 19 payments — averaging $20.81 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Boehringer Ingelheim$351
- GSK$31
- Calliditas Therapeutics US Inc.$14
What the payments were for
- Food & beverage$38297%
- Education$143%
Most of this is food and beverage — typically meals provided during product presentations at a clinic or hospital. Nationally that is the single largest category of reported payments by count.
General payments by program year
Who reported the general payments
Companies are grouped under their corporate parent — a single manufacturer often files under several CMS reporting entities. Research and ownership payments are counted separately and are not in this table.
| Company | Payments | Total |
|---|---|---|
| Boehringer Ingelheim | 17 | $351 |
| GSK | 1 | $31 |
| Calliditas Therapeutics US Inc. | 1 | $14 |
How this compares
$395 in reported general payments places this provider in the 30th percentile of 1,341 nephrology providers in California.
Medicare billing
What this is not: this is the amount Original Medicare Part B allowed for services this provider billed in 2024. It is not their income. It excludes Medicare Advantage — now more than half of all Medicare enrollment — along with Medicaid and all commercial insurance, and it is gross practice revenue before staff, rent, supplies and malpractice premiums. CMS also suppresses any figure covering ten or fewer patients, so low-volume providers appear smaller than they are.
Most prescribed under Part D
| Drug | Claims | Cost to plans & patients |
|---|---|---|
| VelphoroSucroferric Oxyhydroxide | 23 | $41,128 |
| ProsolParenteral Amino Acid 20% No.1 | 41 | $6,356 |
| Sevelamer Carbonate | 23 | $4,535 |
| SpsSodium Polystyrene Sulfon/Sorb | 11 | $1,432 |
| Sodium Polystyrene Sulfonate | 17 | $760 |
| Calcium Acetate | 11 | $681 |
| Midodrine Hcl | 16 | $564 |
| Hydralazine Hcl | 44 | $462 |
| Bumetanide | 24 | $340 |
| Calcitriol | 38 | $214 |
| Furosemide | 48 | $206 |
| Amlodipine Besylate | 33 | $178 |
| Clonidine Hcl | 28 | $164 |
| Potassium Chloride | 13 | $75 |
Paid to pharmacies, not to this prescriber.
Other nephrology in Fountain Valley
- Ajit SawhneyFountain Valley$89K
- Anjay RastogiLos Angeles$2.2M
- Glenn ChertowStanford$2M
- Luis AlvarezPalo Alto$1.8M
- Jose MorfinSacramento$1M
- Rodolfo BatarseRancho Mirage$910K
- Vandana MathurWoodside$769K
- Yasir QaziOrange$618K
- Rafael VillicanaLoma Linda$610K
- Sunil PatelApple Valley$509K
Where these figures come from
- Payments: CMS Open Payments, program years 2019–2025 (publication P06302026_06032026).
- Billing: Medicare Physician & Other Practitioners, data year 2024. Original Medicare Part B only.
- Identity: NPPES NPI Registry, July 2026.