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Dr. Hiroshi Mashimo

Gastroenterology
Boston, MA
35 years experience male

Locations

Office

My office hours

Thursday: 4:00pm - 9:00pm
Show more

Insurances accepted

VA healthcare

Office

Boston, MA

About

Bio

Internal Medicine, Gastroenterology and Hepatology. Practice in Boston, MA. Expertise with >100 top-tier publications in immunology, molecular biology, stem cells, advanced endoscopic imaging (optical coherence tomography, confocal endomicroscopy, magnet-driven capsule imaging) and ablations (radiofrequency- and cryo-ablations, mucosal resections) for early cancers, motility disorders e.g. gastroesophageal reflux disorder, dysphagia, achalasia, gastroparesis, ileus, constipation/diarrhea, IBS, and bowel control disorders.

Specialties
Doctors may have more than one area of specialty interest. Board certification in a specialty area means the doctor has completed formal training and has practice experience in that specialty, and has passed the certification examination from the corresponding accredited medical specialty board.

Gastroenterology

Internal Medicine

Urgent Care

Licenses

United States: Massachusetts

Languages spoken

German, Japanese

Doctor Q&A

130 Answers
21 Agrees
The number of answers this doctor has agreed with.
A 32-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Slow gut: Often two day prep used in patients with known or suspect delayed transit such as those on narcotics, with chronic constipation, and s/p spinal cord ... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 18-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See ur doctor: underlying issue of bulimia needs to be addressed rather than mere coverage with proton pump inhibitors (like omeprazole) and changing what is eaten -... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See your doctor: there are many causes of dysphagia (difficulty swallowing) which may be distinct from causes of odynophagia (pain on swallow), and can be from problem... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 19-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Review w ur doctor: Especially if more frequent or severe, would seek specialty care such as gastroenterologist who can rule out common cases such as food allergies (esp... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 51-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Yes: cecal ulcer is ulcer in the cecum of your colon, where the small intestine and appendix attach. NSAIDs are the most common cause of isolated ulcer in ... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 18-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Likely see Dr: Laxative not advisable as purge, and need to understand root cause if chronic/recurrent constipation. Ad lib laxatives may swing u between constipatio... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 43-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Seek MD attention: causes of left lower belly pain include commonly kidney stones, ovarian cysts, appendicitis, infections, inguinal/femoral hernia, muscle strain, and ... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 38-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See gastroenterology: need better evaluation esp esophageal manometry, pH study (to assess when and how much reflux, also rule out alkaline reflux) beforehand to assess can... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 24-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Reasonable choices: the agents that you mention are quite standard for endoscopy. Diphenhydramine (Benadryl), commonly used for allergies or sleep, when used properly can... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A member asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Discuss w ur doctor: Pain at incision after surgery common, but relation to eating more concerning. Discuss w your doctor underlying cause. Avoid less digestible or fermen... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A member asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Unlikely: Without further details including presence of diabetes/diarrhea and underlying cause of the chronic pancreatitis, i'd say those are drastic measures. ... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 38-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Dep cause/severity: if unable to keep fluids down, and evidence of dehydration, weakness, blood, or fevers, suggest urgent attention by MD - need to r/o other emergent is... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 20-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See your doctor: Unclear what you mean - discharge where? If you mean rectal seepage with diarrhea, suggest first discontinue milk, coffee and artificial sugars, given... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 50-year-old member asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See MD: number of causes for right-sided pain, such as inguinal/femoral hernia, appendicitis, dietary intolerance, and other inflammatory conditions, Would ne... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 35-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Gastroenterologist: Many things may cause this "dyspepsia" such as gastritis/ulcers, gall bladder disease, inflammation, and delayed stomach emptying (gastroparesis). Yo... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 36-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Seek doctor: can be number of causes including reaction to medications, allergies, viral rash, swimming pool rash, etc. and potentially more serious underlying dis... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 45-year-old member asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Many causes- see MD: there are many potential causes for your symptoms. As common as they may be, may warrant evaluation by Gastroenterology specialist, esp if severe, chr... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 29-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See doctor: such degree constipation needs to be addressed - rule out underlying reversible causes such as medication side effects, thyroid/diabetes, dyssynergia ... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 50-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
If recur, see MD: many poorly digested foods or pills can swell and appear strange with diarrhea, but if diarrhea lasts more than a week, should seek medical attention ... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 25-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
GERD alone unlikely: manometric evidence of aperistalsis (not simply on barium test) unlikely from GERD alone, and can be from achalasia or esophageal scleroderma, even wi... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 19-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See MD,chk pregnancy: "morning sickness" may suggest pregnancy and should check for this (such as home urine test kit) or other hormonal or neurological problems and warran... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 56-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Too little info: depends on symptoms, why u r getting those meds, prior lab work, etc. Happy to consult, but appears should get input from ur primary care or consultin... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 28-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Where discharge?: if vaginal discharge, suggest rule out pregnancy if applicable and seek MD ASAP, as could represent possible infection. More urgent if abdominal pain/... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 29-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See doctor: Diarrhea for week w blood certainly need MD attention for stool cultures, and depending on symptoms, possible further tests. Will need more info and h... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 23-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See MD: many causes other than alcohol can lead to elevated ALT including various medications, obesity, diabetes, viral infections, inflammatory conditions of... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 21-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See ur doctor: while these symptoms are common and nebulous, such as viral (e.g. flu) - would see ur doc if persistent/severe, esp for treatable causes. Urgent atten... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 48-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See doctor: this suggests either decreased blood volume (as in dehydration, blood loss, diarrhea) or effective volume (eg vessel dilated from infection, food pois... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 18-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Seek MD if worse: many things can cause - sun exposure, alcohol, anxiety, thyroid disorder, but concerning wud be allergies or infection - latter eso if fever/chills - ... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 40-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See your doctor: this constellation can be consistent with gastroesophageal reflux, but be sure to rule out heart disease (any risks such as chest pain, hi BP, diabete... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See your doctor: if redness is spreading, this should be evaluated by ur doctor for underlying problem such as inflammatory condition or abscess/cellulitis which may r... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 25-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Seek MD: not fully understand ur ? but 6wk abd pain should seek MD, and urgent if with blood anywhere, or fever/chills, nausea/vomit, or worsening. Need to rul... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 29-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See doctor : indeed herpes virus may be underlying cause for both, but there may be other causes underlying her “genital outbreak” and both of you should practice ... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 23-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
"Globus": Referred to as "globus," the lump sensation can correlate w anxiety, but can also share other causes such as acid or volume reflux from stomach into e... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 63-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Further info: Would need further info re medical history, diet, prior stool and blood tests, other medications. Happy to consult but do stop milk/milk products and... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 35-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Followup w ur doc: Wud need more info eg past medical history, present medications, etc. Happy to consult, but avoid milk/milk products, caffeine, sugar substitutes, hig... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 52-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Manometry definition: these are definitions to characterize achalasia (a disorder of esophagus where contraction wave is absent and the lower sphincter does not relax): Typ... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 38-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See ur doctor: given age and assuming no other signif. personal/family history, likelihood hemorrhoids high, but would followup with ur MD re possible flex sigmoidos... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See ur doctor: Various potential causes for ur pain - most commonly inguinal or femoral hernia (worse w strain or incr belly pressure), kidney stones, strained abdom... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Yes: smoking indeed increases blood pressure, both immediately while smoking as well as chronically (i.e., with long-term smoking, can increase BP baseline... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 44-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
PPI, see MD: class of meds called proton pump inhibitors e.g. omeprazole generally more effective if used properly, but the majority of patients are not using it p... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 20-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Would use new: generally good policy not to take expired medications, and I would get fresh antacids, or even try household baking soda if you feel this is from sto... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 38-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
?medicines: Besides foods, the most common reason is medicines that have small capsules within a capsule that enables delivery of the medicine beyond the stomach ... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 34-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Suggest see MD: more info would be needed on medications, underlying conditions e.g. allergies/food intolerances, ethnicity, etc. Be sure checked for pregnancy if ap... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 29-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Dep. severity; fluid: matter of symptoms/severity - not just stool frequency, but also straining, incomplete evacuation, pain/cramp. Severe complications can incl bleeding ... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 38-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Discuss w ur doctor: Right pain less likely relieved w bowel movement, but need to consider more urgent entities such as appendicitis, ovarian cyst, kidney stone if lower ... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 20-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See ur doctor: i'm assuming pregnancy test & urine test (e.g. for infection or trace blood w stones) are negative. unclear what ultrasound looked at - appendix c... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A member asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Depends on cause: Lingering cough could be sign of lung irritation from virus, or even chronic infection by bacteria (bronchitis or pneumonia). These can also lead to a... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 21-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Followup w ur doctor: generally w/o lesions, biopsies not taken unless symptoms or history (e.g. of ulcer) warrant including ruling out H pylori. however given ur age (e... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 28-year-old female asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
Seek medical care: other factors such as family history (of inflammatory conditions and cancer), environmental exposure, and symptoms (associated fevers, diarrhea, const... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 40-year-old male asked:
Dr. Hiroshi Mashimo
Gastroenterology 35 years experience
See ur doctor: Change in bowel habits common, but shouldn't linger months. Common causes: lactose intolerance (from cow milk and products), alcohol/caffeine, artific... Read More
Created for people with ongoing healthcare needs but benefits everyone.

Testimonials
Recommendations and Thank you notes are endorsements given from patients or other doctors.

3
Recommendations
113
Thank you notes
Nov 15, 2015
Dr. Mashimo is a worldwide expert in problems related to GI motility. And he's a really nice guy.
HealthTap member
Mar 31, 2015
Dr. Mashimo is an amazing doctor! #nationaldoctorsday2015 #virtualflower1
HealthTap member
Mar 31, 2015
Dr. Mashimo is an amazing doctor! #nationaldoctorsday2015 #virtualflower1
HealthTap member
This was very helpful. Thanks! Thank you so much! He is getting worse so your answer will help me convince him to get to doctor asap. Thank you again!!
HealthTap member
Thank you, your answer was very helpful! Thanks doc atleast I know there hope and can still have caffeine
HealthTap member
Your answer was very helpful, thanks! Thank you Doctor. Blessings your way.

Education & Training

Medical/Graduate school

Albert Einstein College of Medicine of Yeshiva University, NY
MD

Residency

MASSACHUSETTS GENERAL HOSPITAL

Awards

Top Gastroenterologist , Second Place, Massachusetts - Summer
2013
Most Influential Doctor, Massachusetts - Winter
2015
Thought Leader, Massachusetts - Winter
2015

Affiliations

American Gastroenterlogy Association
American Motility Society
Alpha Omega Alpha Honor Medical Society
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