Doctor profile · Federal record

Dr. Howard Guan, M.D.

Glaucoma Specialist (Ophthalmology) Physician (CMS: Ophthalmology) · Ophthalmology Physician · San Marcos, CA

  • NPI 1134427636
  • Accepts Medicare
  • MIPS 76.4 / 100 · 2023
  • 16 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
340 Rancheros Drive, Suites 164/166
San Marcos, CA 92069
(760) 598-0400
fax (760) 290-7044

Credentials & registration

NPPES · NUCC
NPI registered
March 2011 — 15 yrs on file
Profile last updated
October 21, 2025
Year of graduation
2010 — 16 yrs since
Specialty taxonomy
207WX0009X — NUCC code
State license (1)
California #A119766

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1134427636. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
3,521
Distinct HCPCS
10
Medicare allowed
$263,248
HCPCS Description Services Patients Avg allowed
J2777 Injection, faricimab-svoa, 0.1 mg 1,500 11 $36
99214 Established patient office or other outpatient visit, 30-39 minutes 647 510 $133
92133 Imaging of optic nerve 243 237 $38
92083 Exam of visual field with extended testing 199 192 $67
92250 Photography of the retina 147 144 $41
92134 Imaging of retina 122 106 $44
99213 Established patient office or other outpatient visit, 20-29 minutes 116 99 $95
99204 New patient office or other outpatient visit, 45-59 minutes 81 81 $176
92020 Exam of the internal drainage system of eye 78 77 $30
92014 Established patient complete exam of visual system 53 53 $131

In context: peer comparison

Among 1 peers in San Marcos Glaucoma Specialist (Ophthalmology) Physician, average services per provider: 195. This provider delivers 18× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$946
Transactions
22
Manufacturers
7
Payer (manufacturer) Industry Txns Amount
Abbvie INC. 13 $425.91
Dompe US, INC. 3 $172.22
Carl Zeiss Meditec USA, INC. 2 $167.73
Sight Sciences, INC. 1 $120.00
Apellis Pharmaceuticals, INC. 1 $28.73
Boston Scientific Corporation 1 $16.98
Alcon Vision LLC 1 $14.49

By nature of payment

Food and Beverage
$922
Travel and Lodging
$14
Education
$9

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
4,986
Patients
1,598
Total drug cost
$354,333
Drug Type Claims Patients Total cost
Latanoprost Generic 1,625 442 $44,145
Brimonidine Tartrate Generic 851 234 $28,824
Dorzolamide-Timolol (Dorzolamide Hcl/Timolol Maleat) Brand 766 204 $25,733
Timolol Maleate Generic 500 165 $13,954
Dorzolamide Hcl Generic 301 84 $11,281
Prednisolone Acetate Generic 196 134 $11,552
Alphagan P (Brimonidine Tartrate) Brand 144 47 $65,729
Diclofenac Sodium Generic 143 112 $1,805
Lumigan (Bimatoprost) Brand 95 29 $44,343
Rhopressa (Netarsudil Mesylate) Brand 79 29 $43,930

Frequently asked questions

Auto-generated from federal data
What is Dr. Howard Guan's medical specialty?
Dr. Howard Guan practices Glaucoma Specialist (Ophthalmology) Physician in San Marcos, CA.
Where does Dr. Howard Guan practice?
Dr. Howard Guan practices at 340 Rancheros Drive, San Marcos, CA 92069. Office phone: 7605980400.
What is Dr. Howard Guan's NPI?
Dr. Howard Guan's National Provider Identifier (NPI) is 1134427636, issued by NPPES.
Does Dr. Howard Guan accept Medicare assignment?
Yes. Dr. Howard Guan accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Howard Guan commonly perform?
Top Medicare-reported procedures in 2023: Injection, faricimab-svoa, 0.1 mg (HCPCS J2777); Established patient office or other outpatient visit (HCPCS 99214); Imaging of optic nerve (HCPCS 92133). Source: CMS Medicare Physician & Other Practitioners file.