David Irwin, MD
Neurology · Philadelphia, PANPI 1194986356
Payments from drug & device makers
What this record shows
That places this record below the midpoint for neurology clinicians in PA, where the typical reported total is $778.
No general payments reported
No drug or device maker reported general payments to this provider for 2019–2025. That is a common and unremarkable result.
Across 8 payments — averaging $308,149 each. Payments tied to a research study. These frequently flow through the physician to a hospital or research institution rather than to the physician personally.
- Eli Lilly$2.5M
How this compares
$0 in reported general payments places this provider in the 5th percentile of 941 neurology providers in Pennsylvania.
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 |
|---|---|---|
| Rivastigmine | 26 | $3,340 |
| Quetiapine Fumarate | 110 | $3,140 |
| Galantamine Hbr | 15 | $2,257 |
| Sertraline Hcl | 164 | $1,862 |
| Memantine Hcl | 79 | $1,776 |
| Donepezil Hcl | 128 | $1,556 |
| Olanzapine | 12 | $1,424 |
| Clonazepam | 69 | $1,399 |
| Fluvoxamine Maleate | 14 | $927 |
| Trazodone Hcl | 124 | $801 |
| RivastigmineRivastigmine Tartrate | 15 | $466 |
| Escitalopram Oxalate | 44 | $465 |
| Risperidone | 36 | $452 |
| Mirtazapine | 21 | $364 |
| Divalproex Sodium | 14 | $279 |
Paid to pharmacies, not to this prescriber.
Other neurology in Philadelphia
- Daniel KremensPhiladelphia$1.8M
- Thomas LeistPhiladelphia$1.4M
- Jill Giordano FarmerPhiladelphia$1.2M
- Stephanie Nahas-GeigerPhiladelphia$786K
- Amit Bar-OrPhiladelphia$596K
- Stephen SilbersteinPhiladelphia$428K
- Joseph BergerPhiladelphia$384K
- Sami KhellaPhiladelphia$285K
- Clyde MarkowitzPhiladelphia$274K
- Matthew SternPhiladelphia$251K
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.