Web-based symptom checker and over the counter medication.

In our digital world and modern society, we expect to have access to all sorts of products 24/7. This is also true for health care. People are capable of gathering information about their actual health situation by googling their complaints or by using a web-based symptom checker. To date, there are only a few data on the accuracy and usefulness of the artificial intelligence assisted services.

Referring to an online survey administered to more than 300 users of the Isabel Symptom Checker in the US, most people used the service to better understand the reason for their symptoms and advice if and where to seek care. The authors conclude, that despite concerns about the accuracy of symptom checkers, the user group perceived the service useful for diagnosis.

In a systematic review of 27 studies on digital and online checkers by Chambers et al. (1) the authors describe that diagnostic accuracy was highly variable between different systems and that younger people were more likely to use these services.

There also is web-based information on treatment options including medication. Access to drugs, however, is regulated very differently throughout the world. The US is known for a large number of freely (over the counter, OTC) accessible drugs in stores where not even a pharmacist has a look at it as a safeguard. Therefore, people might buy and ingest drugs far above the limit recommended and with side effects not individually adjusted to their own risk concerning comorbidities and cross- over effects on other drugs taken (e.g. blood-thinning drugs). Top sellers are pain medication (headache) and medication against feverish symptoms.

An example of a top-selling OTC medication in the US is Tylenol with its active ingredient acetaminophen (from https://www.drugs.com/otc/, on January 31st, 11.27 a.m.). It is used as a pain reliever and fever reducer and like paracetamol is liver toxic if taken in too high doses. Therefore, one should avoid taking take it if there already is a known liver disease or if you are frequently drinking alcohol. Also, it might interfere with the common blood-thinning drug warfarin leading to a higher risk of bleeding. A study by Morthorst et al. (2) among European countries revealed that paracetamol (pain medication with dosage depending liver toxic effects)-related inquiries at poison information centers were higher in countries where paracetamol was available in non-pharmacy outlets.

In conclusion, today there is no clear evidence on the accuracy of the web-based diagnostic tools and there can be no recommendation to rely on these artificial intelligence supported services. Concerning over the counter medication, People have to be aware that – although available over the counter and therefore pretending safety – these drugs are not free of risks. This is particularly true if people are taking other medication, do have preexisting illnesses, are pregnant or have allergies against drugs or certain ingredients of drugs. At least, people using OTC medication should carefully read the “Drug Facts” label.

To be sure about the information and recommendations you find on different sources on the internet, always check the references and find websites and sources you trust. The internet is full of articles with misinformation and tips from non-professionals, be sure to check your country’s national health information-website or if in doubt, talk to health-professionals.


1. Digital and online symptom checkers and assessment services for urgent care to inform a new digital platform: a systematic review.

Chambers D, Cantrell A, Johnson M, et al.

Southampton (UK): NIHR Journals Library; 2019 Aug. (Health Services and Delivery Research, No. 7.29.) Available from: https://www.ncbi.nlm.nih.gov/books/NBK545124/ DOI: 10.3310/hsdr07290

2. Availability of Paracetamol Sold Over the Counter in Europe: A

Descriptive Cross-Sectional International Survey of Pack Size Restriction.

Morthorst BR, Erlangsen A, Nordentoft M, Hawton K, Hoegberg LCG. Dalhoff KP

Basic Clin Pharmacol Toxicol. 2018 Jun;122(6):643-649.

doi: 10.1111/bcpt.12959.