Hypoglycemia is a condition of low blood sugar levels. Generally, the doctor in the emergency room won't diagnose hypoglycemia unless the blood sugar level is 50 mg/dl (2.8 mmol/L) or less. People do dangerous things when their blood sugar levels aren't yet that low, however, and many disorders increase the risk of low blood sugar levels.
Antidepressants in the selective serotonin reuptake inhibitor (SSRI) class can trigger hypoglycemia
Drugs like Prozac, Celexa, and Paxil can induce low blood sugar levels even in people who have normal pancreatic function. If you have any eating disorder and you take an SSRI antidepressant, you need to be aware of the symptoms of hypoglycemia.
Olanzapine (Zyprexa) can also induce low blood sugar levels
Olanzapine, which is marketed under the trade name Zyprexa, is a drug in a class known as the atypical antipsychotics. It helps people feel good about themselves, and it is used off-label (without FDA approval) to treat obsessive behavior and to encourage weight gain in anorexia nervosa. There have been reports it can cause excessive excretion of insulin which can lead to dangerously low blood sugar levels.
The combination of infection and anorexia can produce dangerously low blood sugar levels
A number of deaths of anorexia attributed to "inanition", the failure to get nutrition, may actually be due to a combination of infection and nutritional deficits. In anorexia, there are limited stores of glycogen in the liver to produce sugar when it is needed. There are also fewer fat cells that can release fatty acids. Infections interfere with the body's ability to use even its limited supply of glycogen (stored sugar) and fatty acids, and fatality results.
Depression in anorexia may be the result of the 'low blood sugar blues'
The brain runs on glucose. When glucose isn't available, the brain can run on ketone bodies that the body produces from fatty acids, but in anorexia, those fatty acids are not available. Chronic deprivation of glucose can cause depression and Alzheimer's-like symptoms that is easily remedied by the ingestion of sugar, but resisted by people who have anorexia. Anorexia and depression can become a vicious cycle in which the person with anorexia doesn't eat because of depression, and is depressed because of not eating.
Bingeing on sugar, ironically, can be followed by symptoms of hypoglycemia
People who have binge-eating disorder can develop a syndrome similar to hypoglycemia with shakes, mood swings, and even loss of consciousness after they feast on sugary foods and then stop. Scientists speculate that this odd phenomenon is due to the brain's production of dopamine when binge eaters gorge on cookies and cakes and pies and candy and ice cream. When the binge eating is over, the dopamine production falls back to normal, and other brain chemicals predominate, causing anxiety that produces symptoms that look like hypoglycemia.
Self-induced hypoglycemia is a problem in diabetic binge eaters
Some binge eaters become diabetics, and their doctors give them insulin to lower their blood sugar levels. (This is usually a very bad idea, since insulin injections increase appetite. Nonetheless, it is not an unusual practice.) To "cover" their binge eating, these diabetics give themselves extra insulin, but it is not always possible to predict just how much blood sugar levels will rise after eating a given amount of food. And binge eaters usually aren't paying close attention to how much they are eating when they binge. The result of this miscalculation can be self-induced or "factitious" hypoglycemia, despite severe overeating.
Teenagers diagnosed with type 1 diabetes often develop eating disorders
Juvenile diabetes is caused by an autoimmune disorder, not by bad eating habits. (Type 2 diabetes in children and adolescents, on the other hand, is almost always associated with overeating.) However, teens learn to manipulate their blood sugar numbers by taking too much insulin when they eat too much food or by avoiding insulin when they want to "pee away" excess calories by letting the blood sugar levels get too high. Instead of an eating order causing blood sugar dysregulation, abuse of insulin can lead to an eating disorder if the bad diabetes management practices are not corrected.