Marlon C. DeCastro, MD

Accepting New Patients
Offers Video Visits
1162 Montgomery Drive, Suite 2
Santa Rosa, CA 95405
2413.1 miles away
Medical Groups & Affiliations
Providence Medical Network
Speaks: Tagalog and English
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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.

Medical School

University of the Philippines

Internship

Nassau Univ Medical Center- East Meadow

Residency

Nassau Univ. Medical Center- East Meadow

Board Certifications
  • American Board of Internal Medicine, Internal Medicine
Providence Medical Group Santa Rosa - Internal Medicine
1162 Montgomery Drive, Suite 2
Santa Rosa, CA 95405

Medical Groups & Affiliations
Providence Medical Network

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