It’s tempting to ask Doctor Google for advice given how costly and ­annoying the health-care world is. But a recent survey found that online medical advice was reliable less than 40% of the time and actually increased worries for 74% of people who accessed it.

The Internet can be a valuable source of health information—but only if you know where to look…how to determine which medical conditions truly match your symptoms…and what online health advice is best used to supplement treatment from medical professionals, not replace it.

Bottom Line Personal asked Kapil Parakh, MD, MPH, PhD, a practicing doctor, search engine expert and author of the new book Searching for Health, how to best use the Internet to find reliable and appropriate health information and avoid the potential traps…

Write down your symptoms before searching online. Track your symptoms when you don’t feel well, noting what you feel and when and how severely you feel it—“strong burning sensation in throat after dinner,” for example. This written log reduces the odds that you’ll misremember symptoms when you later go online and try to figure out what health problem you might have. You’re probably thinking, I wouldn’t misremember, but it’s surprisingly common for people to convince themselves that they have experienced symptoms when they read about them, in part because many symptoms are subjective—it’s easy to think, I did feel bloated after eating the other day…or I have felt fatigued even if you really didn’t feel any more bloated or tired than usual. Also track the symptom over time—how long have you had it? Does it come and go? Is it growing more ­severe or fading away?

It isn’t just untrained Internet s­earchers who do this—medical students so often convince themselves that they have the diseases they’re studying that this tendency has been dubbed “medical student syndrome” and has ­itself been the subject of medical studies.

Collect potential diagnoses before digging deep into any one. The ­Internet makes it easy to identify diseases that could fit a set of symptoms. Enter a symptom into a search engine such as Google or Bing…or into a “symptom checker” such as Isabel Symptom Checker (…Mayo Clinic Symptom Checker (on, click the “Try the Symptom Checker” button)…or WebMD Symptom Checker (on, scroll down to “WebMD Symptom Checker”), and in seconds, you’ll have a list of potential diagnoses. Rather than getting sidetracked and delving deep into the details of a particular disease, compile a list of diseases that could potentially fit. Sort this list by approximate likelihood, doing your best to factor in not only how well the symptoms seem to fit yours but also how common the condition is in the US…how likely someone of your age, gender and physical health is to get it…and whether it’s a condition that already exists in your medical history and family medical history. Example: If you search for the symptom “loss of feeling in hands and feet,” beriberi, a severe thiamine deficiency, might be among the diseases you come across—but beriberi is extremely rare in the US, except among extreme alcoholics. It should be marked as very unlikely on your list.

Start with a terse search. It’s tempting to enter every symptom you’ve experienced when you use search engines as diagnosis tools. If you have a sharp jabbing pain under your ribs, mild headache and slight stomachache, surely giving Google all of that info increases the odds that the web pages it locates will be about the condition you have, right? Not so! Adding details often detracts from the quality of search engine results. When a search includes more than six to eight symptoms, a high percentage of the results often are from obscure and potentially unreliable websites as the search engine struggles to match all of the search terms. And if a health search includes multiple symptoms, the search engine won’t know to prioritize the main symptom.

Instead, your first search should include only the main symptom you are experiencing and perhaps a detail or two about that symptom. Rather than search “chest pain,” for example, you could search the phrase “jabbing chest pain after eating.” This simple search isn’t necessarily the only search worth trying, but it should be where you start because it’s the least likely to lead you down unhelpful Internet rabbit holes.

Try additional and longer searches only after this simple initial search. Longer searches produce less reliable results, on average, but now and then they do turn up possible diagnoses that shorter searches miss. When you do these longer searches, it’s especially important to pay attention to results that come from only trustworthy websites—more about evaluating the quality of health websites to follow. Details worth adding to the main symptom during subsequent searches include your age or gender, such as “jabbing chest pain after eating for man in his 70s”…details about how long the symptoms have persisted, such as “jabbing chest pain for a week”…medication names—the symptom could be a side effect…or a secondary symptom or two. You could also repeat the search described above, replacing your primary symptom with a different symptom that’s also troubling you. If both of those searches turn up the same potential diagnosis, that could be your answer.

Beware of “symptom ­checker” scares. A study published in The BMJ ­tested 23 online symptom checkers and found that the correct diagnosis was listed first only 34% of the time. The misdiagnoses were not random—most pointed patients toward health problems more serious than they actually had, inducing needless anxiety. Liability concerns are one possible explanation why these web tools tend to favor worst-case scenarios—if someone died after a symptom checker suggested there was no reason for concern, it could lead to a lawsuit. Example: If you enter “chest pain” into a symptom checker, there’s an excellent chance that the first result will be “heart attack” even though there are many less serious health problems that also can cause chest pain.

Use the end of web addresses to gauge the reliability of health information. As a rough rule of thumb, information about health issues found on official government sites ending .gov… the website of the British National Health Service, ending in…or Canadian national health services, ending in—tends to be very reliable. Health info from sites ending .edu or .org usually is trustworthy as well—those generally are the websites of medical schools, hospitals, medical centers and health-related professional organizations, such as the American Heart Association ( There are trustworthy sources of health info ending in the more familiar .com, too— and both do a solid job providing largely accurate info, for example. But proceed with caution when reading health information on unfamiliar .com websites…especially sites that seem to be selling the treatments they’re recommending or community-based message board sites.

Stick with truly trusted sites for info about alternative medicine. There are plenty of effective traditional and alternative treatments—the challenge is determining which ones. These treatments often are not discussed on mainstream health websites, and some have never been proven to be safe and effective in large-scale studies, though many have been “proven” by the test of time. Fortunately, there are a few websites that are very authoritative on alternative medicine, including the sites of the National Center for Complementary and Integrative Health (…The University of Arizona’s Andrew Weil Center for Integrative Medicine (…the National Cancer Institute’s Complementary and Alternative Medicine (…and the National Institutes of Health’s Office of Dietary Supplements (

Find a primary care physician and a pharmacist who are open to alternative treatments, and discuss these treatments before trying them. These professionals can confirm that the treatment is well-regarded and that it won’t interfere with your other prescriptions or treatments.

Health-related personal blogs and social-media posts can be wonderful sources of moral support. It’s easy to feel alone when you have a worrisome symptom or serious health problem—even your loved ones might not understand what you’re going though. On the Internet, you can find blogs and social-media user groups and posts by people who have had symptoms or diagnoses similar to your own. The accuracy of the medical guidance offered on these can be uneven, but the community they offer could be invaluable. Warning: Don’t be frightened if all the blogs or social-media posts that mention your symptom link it to a serious health problem—that’s just the nature of the Internet. If someone has a rash and it turns out to be cancer, he blogs about it…if he has a rash and it clears up in a few days, he forgets about it.

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