Marlon C. DeCastro, MD
Santa Rosa, CA 95405
Providence Medical Group Santa Rosa - Internal Medicine
1162 Montgomery Drive, Suite 2, Santa Rosa, CA 95405
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About Marlon C. DeCastro
As an internist, Dr. DeCastro specializes in providing patient-centered care for adults of all ages. He is board certified in Internal Medicine and able to care for an individual's specific medical needs from preventive services to the diagnosis, treatment and management of acute and chronic conditions and diseases. He is especially adept at treating individuals with diabetes.
Dr. DeCastro received his medical degree from the University of the Philippines in Manila, and conducted an Internal Medicine residency at Nassau University Medical Center in East Meadow, New York. Most recently, Dr. DeCastro served as an attending physician at Clemson Health Center in South Carolina where he provided primary care to adults and served as lead investigator in several studies. While there, he also earned certification in the Diabetes Physician Recognition Program, presented by the National Committee for Quality Assurance.
University of the Philippines
InternshipNassau Univ Medical Center- East Meadow
ResidencyNassau Univ. Medical Center- East Meadow
1162 Montgomery Drive, Suite 2
Santa Rosa, CA 95405
Providence Medical Network
Community Reviews
At Providence, we're dedicated to providing you quality, personalized health care. We are constantly striving to optimize your experience.
As part of ensuring you have a positive experience with Providence, our online provider directory includes ratings and patient comments for select providers. More about our survey.
The BEST.
Providence Patient
I just met this doctor an have not come to any conclusion about care, he does not know me more I off him, that takes time. I have another appointment ( 2) in four months.
Providence Patient
A first!!! The front desk didn't inform the back desk that I had arrived for my appointment. As a result, I waited 40 mins to be seen. Dr DeCastro apologized even though it was not his error. Otherwise, everyone is always kind and conscientious.
Providence Patient
I like this office. Everyone in the last 3 months have been helpful and kind.
Providence Patient
Doctor de castro is helpful in very industrios
Providence Patient
Good analysis and recommendations for my shoulder pain and actions to be taken.
Providence Patient
It was good
Providence Patient
Good
Providence Patient
Dr DeCastro is my primary care provider. It takes months to get an appointment. I wish to see my primary not a NP.
Providence Patient
Great!
Providence Patient
Always late, won't help me with answering question on the phone or through my chart or email. They say I have to make an appointment for everything. I would really like the kind of doctor/patient relationship that I could communicate with my doctor other than making constant appointments
Providence Patient
Dr decastro has lab in medical building but I ave use it [ID] have to to 990 Sonoma lab
Providence Patient
Also great
Providence Patient
He is extremely through. If he can't help me he sends me to someone oho can.
Providence Patient
My father trust Dr. DeCastro
Providence Patient
He did not help!!!! When I picked up the Rx it was a duplicate of what did not work!!!!
Providence Patient
I'm very satisfied with Dr decastro
Providence Patient
My experience was very good.
Providence Patient
He is great - I feel heard at every meeting with him.
Providence Patient
Doctor was matter of fact and it felt like he just wanted to get through the appointment as quickly as possible. Not exactly a warm personality.
Providence Patient
Dr. Decastro Makes me feel more confident and positive about my health and how well I am doing!
Providence Patient
Listened to my concerns and prescribed appropriate meds.
Providence Patient
Dr. DeCastro is a great physician.
Providence Patient
Everything went very well
Providence Patient
Very good experience.
Providence Patient
I am very satisfied with my health care provider.
Providence Patient
Listens and gives advise. Refers me to other Specialty as needed. Good Doctor.
Providence Patient
Dr. De Castro was very thorough and meticulous.
Providence Patient
Everything was to my satisfaction
Providence Patient
I had a good experience with my care provider and I was very satisfied
Providence Patient
Staff and provider seemed unpleasant and lacking good demeanor.
Providence Patient
Dr. DeCastro continues to exceed expectations. An excellent listener, communicator, internist and readily refers me to another specialist as needed.
Providence Patient
My doctor is great
Providence Patient
All Good!
Providence Patient
Great visit
Providence Patient
Dr DeCastro and his staff were great
Providence Patient
Professional
Providence Patient
Very good.
Providence Patient
We are building better rapport as time goes along.i trust him
Providence Patient
So far good experience only
Providence Patient
All worked as it should
Providence Patient
When I couldn"t see my Primary Care provider,a Nurse PractIoner was of great herlp
Providence Patient
Dr Decastro is a top-notch doctor
Providence Patient
Dr DeCastro listens to my concerns, asks pertinent questions and follows through with appropriate referrals/orders. I'm fortunate.
Providence Patient
Not at this time as I want to discuss what bothered me
Providence Patient
I usually walk into the office rather than calling for information, and reception people are usually excellent about answering/helping!!Dr DeCastro was right on it helping with an urgent referral for me to Gynecology no waiting.I am so appreciative of his care!!
Providence Patient
Outstanding service, thank you.
Providence Patient
Dr DeCastro said my creatinine levels were high indicating kidney disease and damage and that I would need kidney transplant or dialysis in the future--greatly upsetting me and causing my AFib to greatly fluctuate. I then made an appoint with my urologist a few days later who said that was ridiculous, my creatinine levels were normal for my age, my kidney health was great and just drink more water. I will be calling to select another GP doctor.
Providence Patient
Dr.decastro was very profiant.
Providence Patient
In the last three months, did you have trouble parking? That would be YES! I get there at 8:30 and lot very crowded. Yet in office building, there's not very many people. I think hospital employees are taking all the parking. Patient should have some kind of reserve parking. Reception desk is like a revolving wheel every time you go there there's someone new. Be nice to see the same people once in a while. Dr. Castro is a very thorough and nice man. Probably one of the better doctors on your staff.
Providence Patient
I'm very satisfied with my provider. Excellent doctor
Providence Patient
He is a good doctor. I feel taken care of.
Providence Patient
Dr. D. Was concerned, caring, approachable-open."Good guy.'
Providence Patient
My appointment was a meet and greet appointment. The doctor was very professional and thorough. I felt that he is a good doctor that will be attentive to my future medical needs.
Providence Patient
Decastro is friendly, listens well, and answers all my questions.
Providence Patient
This was my initial visit ( new patient) with Dr. DeCastro. I was very satisfied with everything about the visit. The doctor had familiarized himself with my medical conditions and was comprehensive in his analysis and recommendations. I look forward to being his patients
Providence Patient
This visit was first visit to change primary care physician. The last primary physician was detached, challenging, and didn't listen or review my file. Dr decastro listened intensely, personally connected with me and accepted my direct style. He reviewed my file before the visit and in step with actions. Given our first interactions I'm feeling very positive I have someone who's collaborating with me.
Providence Patient
Dr. Decastro truly cares about his patients by expressing any concerns he foresee health issues in the future.
Providence Patient
All was good
Providence Patient
Always attentive and professional.
Providence Patient
All in all a positive experience.
Providence Patient
Always a good experience
Providence Patient
He let me feel at ease at all time. Thanks for having him.
Providence Patient
Dr. DeCastro is a very caring, intelligent, informative & all around great Dr. He always makes sure all my concerns are addressed & taken care of
Providence Patient
Excellent service. Dr. Is on top of my medical needs with good recommendations for my health and is excellent on follow up.
Providence Patient
Thoughtful, knowledgeable and well informed. His manner was kind and helpful.
Providence Patient
Dr. Marlon de Castro is a very good Doctor
Providence Patient
I have never been dissatisfied with this office or Dr. DeCastro
Providence Patient
Dr. De has been my GP for 13 years. We have had an up and down relationship. I am Type 2 diabetic. It took10 years before he referred me to a specialist. After many years with an A1C level at [ID] or above, at my last visit to Dr. De, I was [ID]. He didn't say congratulations, or good work. Said it could be dangerous. He's my Dr. Doom and Gloom.
Providence Patient
I'm feeling better about my health.
Providence Patient
He's the most thorough doctor I've ever had and I'm 69 years old
Providence Patient
Dr. Listened and addressed all problems and reviewed all tests and gave recommendations
Providence Patient
Very good
Providence Patient
I was pleased as I was returning from another city and was very relieved for first visit.
Providence Patient
Excellent
Providence Patient
It took over two months to get this appt. I like the doctor
Providence Patient
Dr.Marlon De Castro is the best Doctor.
Providence Patient
Dr DeCastro listens closely to what I have to say. He responds clearly. I have confidence in him as my primary doctor.
Providence Patient
I was amazed at how quickly I got in to see Dr. DeCastro. I usually have to wait and wait. This time it was great!
Providence Patient
No complaints always rcvd the best care on my end
Providence Patient
Excellent!!!
Providence Patient
Everything was great
Providence Patient
Doctor shortage resulted in many months wait to see this doctor as my new primary care physician. I don't expect that will be an issue in the future now that he is my PCP. The visit went very well and he was helpful and showed care for my conditions. Very good doctor.
Providence Patient
Always pleasant. Not condescending, very caring
Providence Patient
I had an early morning appointment; I waited half an hour past the appt time to be seen and then felt like he was trying to catch up by shortchanging the time he spent with me.
Providence Patient
I was very satisfied
Providence Patient
Am always satisfied and reassured about my healthcare
Providence Patient
All was good. I have not challenged Dr. DeCastro with any major problems.
Providence Patient
You all are doing a great job!!!
Providence Patient
Over the years I've found that just about any health care professional fixates on something and rarely listens to anything else. I feel that I could go in with a compound fracture and it would be ignored while the provider talked about weight or cholesterol.
Providence Patient
I am a new patient.
Providence Patient
A very good doctor.
Providence Patient
He insists on keeping a mask on. I find it difficult to understand him and have told him so on numerous occasions. My other two doctors at Providence aren't hung-up on masks, and we communicate!
Providence Patient
Very good.
Providence Patient
Very good.
Providence Patient
Dr. DeCastro is a good and kind doctor who fully makes sure I understand my health issues
Providence Patient
Dr DeCastro is a compassionate and trustworthy physician. He is very knowledgeable and has excellent bedside manners.
Providence Patient
Dr. DeCastro is the best. You don't feel rushed, and he wants to know my concerns, and give clear answers.
Providence Patient
Great Team
Providence Patient
Always a good experience
Providence Patient
Everything went well, also received shingles #2 and flu shot
Providence Patient
I am very satisfied with Dr DeCastro and the medical team.
Providence Patient
I had all my questions and concerns addressed at this appointment. Thank you Dr.DeCastro and wonderful staff!!
Providence Patient
Was reminded that I didn't get my labs done ,mainly for my prescriptions ,and I appreciate that and will do them very soon for our records.also will follow up with a dermatologist as recommended.
Providence Patient
Great
Providence Patient
Everything was good.
Providence Patient
All is good
Providence Patient
The doctor was impatient when I responded to two of his questions. The explanations, in my opinion, were necessary to he could clearly understand the situation . I was a bit annoyed that he seemed inpatient.
Providence Patient
On point, respectful and friendly
Providence Patient
Good doctor
Providence Patient
Dr DeCastro is very thorough
Providence Patient
I've worked/volunteered in health sciences & appreciate the details - everyone is very professional & attentive. Very fortunate to have them ALL there for me!
Providence Patient
He was great reached out with follow up labs sn xrays results as soon as they were available
Providence Patient
He is knowledgeable, kind, responsive.
Providence Patient
Dr. DeCastro is stellar; I have referred him to friends needing a physician. He is the best! Easy to understand, very thorough, and comprehensive in everything.
Providence Patient
This was my initial visit with my provider, establishing a relationship for ongoing care.I found the physician to be knowledgeable, friendly, and easy to talk with sharing my current medical condition in past history.I found the doctor to be
Providence Patient
I was treated with courtesy and respect which I really appreciate. Thank you kindly.
Providence Patient
Everything is fine.
Providence Patient
Listen to your patients concerns
Providence Patient
I had a nice experience.
Providence Patient
It is a real comfort to know that my physicians truly care about my care!Thank you!
Providence Patient
Dr DeCastro is always kind, professional and aware of my health history. He is very good at looking at the whole picture not just separate unrelated issues. It's not always easy to schedule an appointment with him but that seems to be the norm for all offices.
Providence Patient
Good job Doc
Providence Patient
Dr DeCastro is thorough and professional. A great internist. I refer all my friends and patients to him.
Providence Patient
Providence and doctor to Castro take very good care of me I'm extremely satisfied
Providence Patient
Dr. De Castro listened carefully and thoughtfully to my health concerns and and gave helpful responses. His manner is both friendly and professional.
Providence Patient
I felt I was given excellent care. My concerns were addressed promptly.
Providence Patient
First time seeing Dr. Decastro. Much better experience than a previous visit at another health care system. I felt like he actively listened and explained his thought process about diagnostics and treatment for a health concern I am having.
Providence Patient
My care provider Dr Marlon DeCastro is very professional about his job and treats me as a patient thoroughly and gives me time to ask questions. In fact, he asked me if I have any questions for him before I leave in case there's anything that I might be concerned about that we hadn't gone over yet. He's kind he's thorough. He's great at diagnosing do bloodwork. I've noticed that about him and I appreciate that about him with both myself and my husband and what can I say he is a good example of what a medical facility should be about, giving great care and caring while giving it.
Providence Patient
He is good doctor always hear all my question and answer cjearly . Thank you .
Providence Patient
Clinical Interests
- Abdominal Cramps
- Abdominal Pain
- Abnormal Bowel Movement
- Abnormal Stool
- Abrasion
- Acne
- Actinic Cheilitis
- Acute Arthritis
- Acute Back Pain
- Aging
- Alcohol Dependency
- Allergic Conjunctivitis
- Allergic Contact Dermatitis
- Allergic Reaction
- Allergic Rhinitis
- Allergic Wheezing
- Allergies
- Altered Bowel Habits
- Anal Pain
- Anemia
- Angular Cheilitis
- Animal Bite
- Ankle Injury
- Ankle Instability
- Anorexia
- Anxiety
- Aphthous Ulcers
- Arm Pain
- Arm Weakness
- Arthralgia
- Asthma
- B12 Deficiency Anemia
- Back Injury
- Back Muscle Injury
- Back Muscle Pain
- Back Pain
- Bereavement
- Bilateral Knee Pain
- Birthmark
- Bleeding Hemorrhoids
- Blister
- Blood In Stool
- Blurred Vision
- Breast Lump
- Bright Red Blood Per Rectum
- Bronchitis
- Bruising
- Burns
- Cancer Prevention
- Cancer Screening
- Cardiovascular Disease
- Cellulitis
- Cerumen Removal
- Chest Pain
- Chlamydia
- Choking Sensation
- Cholesterol Disorders
- Cholesterol Management
- Chronic Abdominal Pain
- Chronic Cough
- Chronic Diarrhea
- Chronic Disease Management
- Chronic Fatigue Syndrome (Cfs)
- Chronic Migraines
- Chronic Obstructive Pulmonary Disease
- Chronic Pain
- Claudication
- Cold Intolerance
- Cold Sore
- College Health
- Common Cold
- Concussion
- Concussion Testing
- Confusion
- Conjunctivitis
- Constant Nausea
- Constipation
- Contact Dermatitis
- Coping Skills
- Cough
- Cystitis
- Daytime Sleepiness
- Decrease In Appetite
- Dehydration
- Dementia
- Depressed Mood
- Dermatophytosis
- Diabetes Education
- Diabetes Management
- Diabetes Mellitus
- Diarrhea
- Diet And Exercise
- Diet And Nutrition
- Disability Evaluation
- Disorder Of Balance
- Distractible
- Diverticulitis
- Dizziness
- Drug Reaction
- Dry Nose
- Dry Scalp
- Dry Sinus
- Dry Skin
- Dyshidrosis
- Dyspepsia
- Dysphagia
- Dysphoria
- Dyspnea On Exertion
- Dysuria
- Ear Discharge
- Ear Drainage
- Ear Exam
- Ear Infections
- Ear Pressure
- Earache
- Eczema
- Elbow Pain
- Elbow Sprain
- Emphysema
- Employee Health
- Enlarged Prostate
- Environmental Allergies
- Epicondylitis
- Epigastric Pain
- Epistaxis
- Eructation
- Erythema
- Eye Infections
- Eye Pain
- Eye Strain
- Face Swelling
- Facial Nerve Palsy And Paresis
- Facial Pain
- Facial Tingling
- Falls
- Family History Of Cancer
- Family History Of Heart Disease
- Fasciculations
- Fatigue
- Fecal Incontinence
- Fever
- Fever With Chills
- Finger Pain
- First Degree Burns
- Flu Shot Vaccination
- Folliculitis
- Food Poisoning
- Foot Injury
- Foot Pain
- Frailty
- Frequency Of Urination
- Frequent Urinary Tract Infections
- Gastric Ulcer
- Gastroenteritis
- Gastroesophageal Reflux Disease
- Genital Herpes, Female
- Genital Herpes, Male
- Genital Warts
- Geriatrics
- Gluten Sensitivity
- Gout
- Grief
- Groin Mass
- Groin Pain
- Hand Injury
- Hand Pain
- Head Congestion
- Headache
- Health Maintenance
- Hearing Loss
- Heart Disease
- Heart Murmur
- Heart Racing
- Heat Intolerance
- Heel Pain
- Hematochezia
- Hematuria
- Hemoptysis
- Hemorrhoids
- Hepatitis A Vaccination
- Hepatitis B Vaccination
- Hernia
- Herpes
- Herpes Zoster
- Herpetic Whitlow
- Hip Pain
- Hirsutism
- Hoarseness
- Human Papilloma Virus (Hpv) Vaccination
- Hyperglycemia
- Hypertension
- Hypothyroidism
- Impacted Cerumen
- Impetigo
- Infectious Mononucleosis
- Influenza
- Ingrown Hair
- Ingrown Nail
- Insect Allergy
- Insulin Resistance
- Intention Tremor
- Interstitial Cystitis
- Intertrigo
- Iron Deficiency Anemia
- Itchy Ear
- Jaundice
- Joint Stiffness
- Joint Swelling
- Joint Warmth
- Keloid
- Keratin Cyst
- Keratitis
- Keratosis Pilaris
- Knee Click
- Knee Injury
- Knee Pain
- Labyrinthitis
- Lactose Intolerance
- Laryngitis
- Lateral Epicondylitis
- Leg Numbness
- Leg Pain
- Leg Weakness
- Lethargy
- Lifestyle Modification
- Lipomas
- Lower Back Pain
- Lump In Throat
- Lyme Disease
- Lymphadenopathy
- Measles Vaccination
- Medial Epicondylitis
- Memory Disorders
- Meningitis Vaccination
- Mens Health
- Migraine
- Mmr Vaccine
- Mood Symptoms
- Motion Sickness
- Mouth Bleeding
- Mouth Pain
- Mouth Ulcer
- Muscle Cramps
- Muscle Strain
- Muscle Weakness
- Musculoskeletal Pain
- Myalgia
- Nail Disease
- Nasal Congestion
- Nasal Obstruction
- Nausea
- Neck Muscle Injury
- Neck Pain
- Neck Sprain
- Noisy Breathing
- Norovirus
- Nose Pain
- Numbness
- Nutrition And Health
- Nutritional Counseling
- Obesity
- Odynophagia
- Optic Migraines
- Orthopnea
- Orthostatic Hypotension
- Osteoarthritis
- Osteopenia
- Osteoporosis
- Otalgia
- Otitis
- Overweight
- Palpitations
- Panic Reaction
- Paresthesia
- Paronychia
- Patellofemoral Syndrome
- Penile Bleeding
- Persistent Cough
- Pharyngitis
- Plantar Fasciitis
- Pleurisy
- Pleuritic Pain
- Pneumonia
- Pneumonia Vaccination
- Poison Ivy
- Poison Oak
- Polypharmacy
- Positional Vertigo
- Post Nasal Drip
- Prediabetes
- Preventive Medicine
- Problems With Smell And Taste
- Prostate Cancer Screening
- Prostate Examination
- Prostate Specific Antigen Blood Test
- Pruritus
- Pulmonary Infections
- Pyelonephritis
- Rash
- Rectal Bleeding
- Rectal Pain
- Restless Legs Syndrome
- Rhinitis
- Rosacea
- Scab
- Scabies
- Scaly Skin
- Sciatica
- Scratchy Voice
- Seasonal Allergies
- Seborrheic Dermatitis
- Sensitive Skin
- Severe Asthma
- Sexually Transmitted Disease (Std)
- Shingles Vaccination
- Shortness Of Breath (Sob)
- Shoulder Pain
- Shoulder Sprain
- Shoulder Strain
- Sinus Pain
- Sinus Pressure
- Sinusitis
- Skin Abscess
- Skin Cancer Screening
- Skin Tag Removal
- Sleep Disorders
- Slowing Of Urinary Stream
- Smoker Cough
- Snoring
- Sore Throat
- Spider Bite
- Splinter Removal
- Sports Related Concussion Testing
- Sprain
- Sputum Production
- Stomach Cramps
- Stomach Pain
- Straining On Urination
- Strep Throat
- Stress Incontinence
- Stridor
- Stye
- Substance Addiction
- Sunburn
- Suture Removal
- Swallowing Problem
- Syncope
- Tachycardia
- Tension Headache
- Testicular Pain
- Throat Tightness
- Thumb Dislocation
- Thyroid Disorder
- Tick Borne Infections
- Tinea Corporis
- Tinea Pedis
- Tingling
- Tinnitus
- Tobacco Use Cessation
- Tongue Pain
- Tongue Swelling
- Tracheobronchitis
- Travel Medicine
- Traveler's Diarrhea
- Tremor
- Tuberculosis (Tb) Test
- Twitching
- Type 1 Diabetes
- Type 2 Diabetes
- Unsteady Gait
- Upper Back Pain
- Upper Respiratory Infection
- Urge Incontinence
- Urinary Hesitation
- Urinary Retention
- Urinary Tract Infection
- Urinary Urgency
- Urticaria
- Vaccinations
- Varicella
- Varicella Vaccination
- Vasovagal Syncope
- Vertigo
- Viral Conjunctivitis
- Virtual Care
- Visual Discomfort
- Visual Disturbance
- Vitamin D Deficiency
- Vitamin Deficiency
- Voice Problems
- Vomiting
- Warts
- Weakness
- Weight Loss
- Weight Problem
- Wellness
- Wheezing
- Wrist Pain
- Wrist Sprain
Doctor DeCastro is quite thorough and explains things well. I am pleased to be under his care.
Providence Patient