Go general, head to toe, then neuro, and if you know what you're looking for, you will better be able to figure out what questions to ask. Here's a quick example - it'll be short and incomplete since my brain is slowly entering hibernation as graduation draws near! -
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General: Look for cancer, thyroid, sepsis... Any fever/chills, night sweats, weight changes (especially loss, and know how much in, say, a month), heat/cold intolerance, hair/nail changes, episodes of syncope/vertigo/orthostatic hypotension, appetite, sleep disturbance
Head: Blurry/double vision, tinnitis/ear pain, dysphagia, neck stiffness
Lungs: Dyspnea.
Cardiac/Chest: Palpitations, tachycardia, chest DISCOMFORT (which includes pain AND atypical MI/GERD, referred pneumonia, etc.) How many pillows do you sleep with. Leg swelling.
GI: Diarrhea, constipation, blood in stool, abdominal pain, incontinence
GU: Dysuria, frequency, discharge, urgency, incontinence, blood in urine
Muscle/Skin: Joint pain/swelling, muscle pain, rashes
Neuro: Paresthesias, numbness, loss of strength, ataxia
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