Doctor profile · Federal record

Dr. William Farnsworth, M.D.

Neurology Physician (CMS: Neurology) · Carlsbad, CA

  • NPI 1669827028
  • Accepts Medicare
  • 10 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

Operates at 3 locations .

NPPES Updated May 11, 2026
Primary practice
6010 Hidden Valley RD Ste 200
Carlsbad, CA 920114219
(760) 631-3000
fax (760) 270-9534
Additional location
1955 Citracado Pkwy Ste 102
Escondido, CA 920294111
Additional location
31515 Rancho Pueblo RD Ste 104
Temecula, CA 925924837

Credentials & registration

NPPES · NUCC
NPI registered
May 2016 — 10 yrs on file
Profile last updated
September 10, 2025
Year of graduation
2016 — 10 yrs since
Specialty taxonomy
2084N0400X — NUCC code
State license (1)
California #A172324

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1669827028. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
7,488
Distinct HCPCS
10
Medicare allowed
$187,644
HCPCS Description Services Patients Avg allowed
J0585 Injection, onabotulinumtoxina, 1 unit 6,500 27 $6
99214 Established patient office or other outpatient visit, 30-39 minutes 278 219 $137
99215 Established patient office or other outpatient visit, 40-54 minutes 172 150 $191
99205 New patient office or other outpatient visit, 60-74 minutes 121 121 $232
99233 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 116 51 $123
99213 Established patient office or other outpatient visit, 20-29 minutes 103 96 $97
G2212 Prolonged office or other outpatient evaluation and management service(s) beyond the maximum required time of the primary procedure which has been selected using total time on the date of the primary service; each additional 15 minutes by the physician or 77 68 $34
99204 New patient office or other outpatient visit, 45-59 minutes 56 56 $177
64615 Injection of chemical for paralysis of facial and neck nerve muscles on both sides of face 32 26 $160
99223 Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 22 22 $179

In context: peer comparison

Among 9 peers in Carlsbad Neurology Physician, average services per provider: 1,345. This provider delivers 5.6× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$2,180
Transactions
103
Manufacturers
15
Payer (manufacturer) Industry Txns Amount
Abbvie INC. 35 $827.38
Pfizer INC. 15 $163.76
Lundbeck LLC 11 $157.94
Acadia Pharmaceuticals INC 8 $136.91
Eisai INC. 6 $131.71
Neurocrine Biosciences, INC. 4 $97.56
Amneal Pharmaceuticals LLC 4 $91.06
Averitas Pharma INC. 3 $85.11
Grifols USA, LLC 4 $70.24
Lilly USA, LLC 3 $65.81
Neurelis, INC. 3 $61.00
Ucb, INC. 3 $60.41
Biogen, INC. 2 $46.92
Otsuka America Pharmaceutical, INC. 1 $29.77
Takeda Pharmaceuticals U.S.A., INC. 1 $24.56

By nature of payment

Food and Beverage
$2,153
Education
$27

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
991
Patients
270
Total drug cost
$220,385
Drug Type Claims Patients Total cost
Memantine Hcl Generic 193 62 $13,028
Donepezil Hcl Generic 180 71 $3,862
Carbidopa-Levodopa (Carbidopa/Levodopa) Brand 120 36 $6,839
Gabapentin Generic 104 25 $2,833
Levetiracetam Generic 63 17 $1,805
Olanzapine Generic 60 17 $5,247
Quetiapine Fumarate Generic 50 11 $1,441
Atorvastatin Calcium Generic 43 19 $693
Nurtec Odt (Rimegepant Sulfate) Brand 42 12 $59,135
Divalproex Sodium Generic 29 0 $2,376

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. William Farnsworth's medical specialty?
Dr. William Farnsworth practices Neurology Physician in Carlsbad, CA.
Where does Dr. William Farnsworth practice?
Dr. William Farnsworth practices at 6010 Hidden Valley RD Ste 200, Carlsbad, CA 920114219. Office phone: 7606313000.
What is Dr. William Farnsworth's NPI?
Dr. William Farnsworth's National Provider Identifier (NPI) is 1669827028, issued by NPPES.
Does Dr. William Farnsworth accept Medicare assignment?
Yes. Dr. William Farnsworth accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. William Farnsworth commonly perform?
Top Medicare-reported procedures in 2023: Injection, onabotulinumtoxina, 1 unit (HCPCS J0585); Established patient office or other outpatient visit (HCPCS 99214); Established patient office or other outpatient visit (HCPCS 99215). Source: CMS Medicare Physician & Other Practitioners file.