Self-diagnosis is the process of diagnosing, or identifying, medical conditions in oneself. It may be assisted by medical dictionaries, books, resources on the Internet, past personal experiences, or recognizing symptoms or medical signs of a condition that a family member previously had. For internet searching, it helps to know medical terms for the various signs and symptoms.
Self-diagnosis is prone to error and may be potentially dangerous if inappropriate decisions are made on the basis of a misdiagnosis. Because of the risks, self-diagnosis is officially discouraged by governments, physicians, and patient care organizations. Even physicians are discouraged from engaging in self-diagnosis, because doctors also make mistakes in diagnosing themselves. If the self-diagnosis is wrong, then the misdiagnosis can result in improper health care, including wrong treatments and lack of care for serious conditions.
One of the greatest dangers of self diagnosis in psychological syndromes, is that you may miss a medical disease that masquerades as a psychiatric syndrome. Self-diagnosis also undermines the role of the doctor-which is not the best way to start the relationship. Then there is the fact that we can know and see ourselves, but sometimes, we need a mirror to see ourselves more clearly. By self-diagnosing, you may be missing something that you cannot see. Another danger of self diagnosis is that you may think that there is more wrong with you than there actually is. Self-diagnosis is also a problem when you are in a state of denial about your symptoms.— 
However, self-diagnosis may be appropriate under certain circumstances. All over-the-counter (non-prescription) medications are offered on the assumption that people are capable of self-diagnosis, determining first that their condition is unlikely to be serious and then the possible harm caused by incorrect medication minor. Some conditions are more likely to be self-diagnosed, especially simple conditions such as head lice and skin abrasions or familiar conditions such as menstrual cramps, headache or the common cold.
Complex conditions for which medications are heavily advertised, including conditions like ADHD in adults, present a more challenging situation. Direct-to-consumer marketing of medications is widely criticized for promoting inappropriate self-diagnosis. One other condition that is commonly self-diagnosed is gluten intolerance.
- Medical signs: what an observer can see such as skin diseases (dermatitis, warts, blisters, etc.) or urine color changes (urinalysis), feel...such as fever, or hear, or smell on or in the patient. Diarrhea and constipation are signs with numerous causes and even non-medical people can see from the examples on the Bristol Stool Chart.
- Medical Symptoms: what the patient describes about the ailment (list of medical symptoms such as pain).
- Medical tests, to include naked eye (gross) exams of urine, sputum, and stool (feces...see Bristol Stool Chart)
- Can include personal attempts to get referral to a clinic in the Undiagnosed Diseases Network
- Can include personal attempts to learn of rare disease TV episodes and organizations for ideas on where to get an accurate diagnosis.
- Can include personal attempts to have your physician order comprehensive genetic testing by way of specimen sent in for such as Emory Genetic Lab's EmExome testing for genetic based disease as the basis for your illness.
- Medical statistics
- Medical prognosis (prediction of the outcome)
- Home remedy
- Related mental disorders:
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