Many people suffer from painful medical conditions. According to MedlinePlus, a service of the U.S. National Library of Medicine and the National Institutes of Health, pain is a sensation that's triggered by a person's nervous system, and pain can be sharp or dull and constant or intermittent. MedlinePlus states that a person can experience focal or diffuse pain, and that pain is the body's way of telling a person that something is wrong. Certain medical conditions generate excessive amounts of pain.
Shingles
Shingles is one of the most painful medical conditions. According to the National Institute of Neurological Disorders and Stroke, a division of the National Institutes of Health, shingles or herpes zoster is characterized by an outbreak of rash or blisters on a person's skin, and shingles is caused by the varicella-zoster virus. NINDS notes that burning or tingling pain, along with numbness or itching, are among the first shingles-related symptoms to appear, and that the pain or discomfort manifests in one part---and on only one side---of the the body. After several days, fluid-filled blisters appear on the skin. According to NINDS, shingles-related pain ranges from mild to severe, and some people experience excruciating pain from even minor skin contact or a breeze over the affected area. Shingles often appear in a band-like distribution, or dermatome, on one side of the trunk, around a person's waistline.
Kidney Stones
Passing a kidney stone is one of the most painful medical conditions. The National Institute of Diabetes and Digestive and Kidney Diseases, a division of the National Institutes of Health, states that kidney stones---hard masses or crystal aggregations---are one of the most painful urologic disorders, and that the first symptom of a kidney stone is often extreme pain that arises without warning. A person with kidney stones will usually experience a sharp, cramping pain in his low back and flank or lower abdomen, along with nausea and vomiting and pain that eventually spreads to his groin. According to the NIDDK, the cause of kidney stones is often difficult to determine, and while some types of foods may promote stone formation, it's unclear whether eating certain foods causes kidney stones in people who are not susceptible. Susceptible individuals include people with a family history of kidney stones, people with urinary tract infections and people with hyperparathyroidism.
Migraine
Migraine is one of the most painful medical conditions. According to the National Headache Foundation---the world's largest voluntary organization for the support of headache sufferers---migraine affects almost 30 million Americans and can cause extreme pain. The NHF states that migraine pain occurs when the trigeminal nerve---one of 12 pairs of cranial nerves---releases chemical irritants that cause brain blood vessels to swell. Swollen brain blood vessels generate pain signals, which are sent to the brain stem for processing. Migraine-related pain is referred pain, or pain that originates in one part of the body but manifests elsewhere, especially around a person's eye, temple, face, sinus, jaw or neck. According to the NHF, once a migraine is full-blown, a migraineur will exhibit extreme sensitivity in the face and head region, and any activity that involves head contact, such as combing the hair, can be painful.
