Doxycycline and Canker sores - a phase IV clinical study of FDA data


Canker sores is found among people who take Doxycycline, especially for people who are male, 60+ old, have been taking the drug for < 1 month.

The phase IV clinical study analyzes which people take Doxycycline and have Canker sores. It is created by eHealthMe based on reports of 53,763 people who have side effects when taking Doxycycline from the FDA, and is updated regularly. You can use the study as a second opinion to make health care decisions.

Phase IV trials are used to detect adverse drug outcomes and monitor drug effectiveness in the real world. With medical big data and AI algorithms, eHealthMe is running millions of phase IV trials and makes the results available to the public. Our original studies have been referenced on 600+ medical publications including The Lancet, Mayo Clinic Proceedings, and Nature.

On Oct, 01, 2022

53,763 people reported to have side effects when taking Doxycycline.
Among them, 22 people (0.04%) have Canker sores.

What is Doxycycline?

Doxycycline has active ingredients of doxycycline hyclate. It is often used in acne. eHealthMe is studying from 56,911 Doxycycline users for its effectiveness, alternative drugs and more.

What is Canker sores?

Canker sores (painful, open sore in the mouth) is found to be associated with 1,361 drugs and 991 conditions by eHealthMe.

Number of Doxycycline and Canker sores reports submitted per year:

Could Doxycycline cause Canker sores?

Time on Doxycycline when people have Canker sores *:

  • < 1 month: 100 %
  • 1 - 6 months: 0.0 %
  • 6 - 12 months: 0.0 %
  • 1 - 2 years: 0.0 %
  • 2 - 5 years: 0.0 %
  • 5 - 10 years: 0.0 %
  • 10+ years: 0.0 %

Gender of people who have Canker sores when taking Doxycycline *:

  • female: 50 %
  • male: 50 %

Age of people who have Canker sores when taking Doxycycline *:

  • 0-1: 0.0 %
  • 2-9: 0.0 %
  • 10-19: 7.14 %
  • 20-29: 7.14 %
  • 30-39: 14.29 %
  • 40-49: 7.14 %
  • 50-59: 28.57 %
  • 60+: 35.71 %

Common drugs people take besides Doxycycline *:

  1. Metformin: 4 people, 18.18%
  2. Calcium: 4 people, 18.18%
  3. Adderall: 3 people, 13.64%
  4. Vitamin D3: 3 people, 13.64%
  5. Percocet: 3 people, 13.64%
  6. Probiotic: 3 people, 13.64%
  7. Vitamin B12: 3 people, 13.64%
  8. Vitamin C: 3 people, 13.64%
  9. Magnesium: 3 people, 13.64%
  10. Xyrem: 3 people, 13.64%

Common side effects people have besides Canker sores *:

  1. Drug Ineffective: 6 people, 27.27%
  2. Breathing Difficulty: 6 people, 27.27%
  3. Nausea (feeling of having an urge to vomit): 5 people, 22.73%
  4. Itching: 5 people, 22.73%
  5. Urinary Tract Infection: 5 people, 22.73%
  6. Oral Candidiasis (fungal infection of mouth): 4 people, 18.18%
  7. Anaemia (lack of blood): 4 people, 18.18%
  8. Diarrhea: 4 people, 18.18%
  9. Stress And Anxiety: 3 people, 13.64%
  10. Fatigue (feeling of tiredness): 3 people, 13.64%

Common conditions people have *:

  1. Urinary Tract Infection: 4 people, 18.18%
  2. Interstitial Lung Disease: 3 people, 13.64%
  3. Rashes (redness): 3 people, 13.64%
  4. Immunodeficiency Disorders: 3 people, 13.64%
  5. Pain: 2 people, 9.09%
  6. Narcolepsy (brain's inability to regulate sleep-wake cycles normally): 2 people, 9.09%
  7. Chlamydial Infection (a common sexually transmitted infection (sti) in humans caused by the bacterium chlamydia trachomatis): 1 person, 4.55%
  8. Depression: 1 person, 4.55%
  9. Dermatitis Atopic (inflammatory, chronically relapsing, non-contagious and pruritic skin disorder): 1 person, 4.55%
  10. Fungal Infection: 1 person, 4.55%

* Approximation only. Some reports may have incomplete information.

Do you take Doxycycline and have Canker sores?

Check whether Canker sores is associated with a drug or a condition

How to use the study?

You can discuss the study with your doctor, to ensure that all drug risks and benefits are fully discussed and understood.

Related studies

How severe was Canker sores and when was it recovered:

Expand to all the drugs that have ingredients of doxycycline hyclate:

Alternative drugs to, pros and cons of Doxycycline:

Common Doxycycline side effects:

Browse all side effects of Doxycycline:

a b c d e f g h i j k l m n o p q r s t u v w x y z

Canker sores treatments and more:

COVID vaccines that are related to Canker sores:

Common drugs associated with Canker sores:

All the drugs that are associated with Canker sores:

Common conditions associated with Canker sores:

All the conditions that are associated with Canker sores:

How the study uses the data?

The study uses data from the FDA. It is based on doxycycline hyclate (the active ingredients of Doxycycline) and Doxycycline (the brand name). Other drugs that have the same active ingredients (e.g. generic drugs) are not considered. Dosage of drugs is not considered in the study.

Who is eHealthMe?

With medical big data and proven AI algorithms, eHealthMe provides a platform for everyone to run phase IV clinical trials. We study millions of patients and 5,000 more each day. Results of our real-world drug study have been referenced on 600+ medical publications, including The Lancet, Mayo Clinic Proceedings, and Nature. Our analysis results are available to researchers, health care professionals, patients (testimonials), and software developers (open API).


WARNING: Please DO NOT STOP MEDICATIONS without first consulting a physician since doing so could be hazardous to your health.

DISCLAIMER: All material available on is for informational purposes only, and is not a substitute for medical advice, diagnosis, or treatment provided by a qualified healthcare provider. All information is observation-only. Our phase IV clinical studies alone cannot establish cause-effect relationship. Different individuals may respond to medication in different ways. Every effort has been made to ensure that all information is accurate, up-to-date, and complete, but no guarantee is made to that effect. The use of the eHealthMe site and its content is at your own risk.

If you use this eHealthMe study on publication, please acknowledge it with a citation: study title, URL, accessed date.

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