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Overview |
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Definition |
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Hypoglycemia is characterized by an inadequate concentration of glucose in
circulating blood (low blood sugar). Beta cells in the pancreas secrete the
hormone insulin after meals in response to an increase in plasma glucose
concentrations. Insulin, in turn, lowers plasma glucose concentrations by
increasing the rate at which glucose is taken up by cells. A deficiency of
plasma glucose (e.g., after exercise, during pregnancy) because of increased
glucose utilization causes the alpha cells of the pancreas to secrete the
hormone glucagon. Glucagon, in turn, stimulates the release of glucose that is
stored in the liver as glycogen to make up for the deficit. These
glucoregulatory mechanisms can become overworked by lifestyle factors such as
stress or poor diet, or by disease, or as a result of genetic
predisposition.
Hypoglycemia is typically divided into two categories: fasting
(postabsorptive) hypoglycemia and reactive (postprandial) hypoglycemia. Fasting
hypoglycemia is associated with medications (e.g., sulfonylureas) and serious
disease states (e.g., critical organ failure, various cancers, prolonged
starvation). Reactive hypoglycemia is associated with postprandial hypoglycemia
that becomes symptomatic several hours after a meal, and often with exercise. It
is usually not associated with a serious preexisting
disorder. |

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Etiology |
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Reactive causes include:
- Fasting hypoglycemia
- Prolonged starvation
- Postprandial hypoglycemia, especially with exercise
- Gastric surgery
Fasting (postabsortive) causes include:
- Drugs (e.g., insulin, sulfonylureas, alcohol)
- Organ failure (e.g., renal, cardiac, or hepatic failure)
- Hormone deficiencies (e.g., growth hormone, cortisol)
- Endogenous hyperinsulinism (e.g., insulinoma)
- Non-beta cell tumors (e.g., fibrosarcoma, mesothelioma)
- Congenital enzyme abnormalities (e.g., glycogen storage disease type
1)
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Risk Factors |
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- Diabetes (especially insulin excess and impaired glucose
counter-regulation)
- Excessive use of alcohol, tobacco, coffee, or caffeine-containing
drinks
- Treatment for diabetes (e.g., sulfonylureas)
- Cancer
- Poor diet (e.g., excessive intake of simple carbohydrates and/or
inadequate protein intake)
- Congenital enzyme abnormalities
- Severe illness (e.g., organ failure,
sepsis)
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Signs and Symptoms |
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Clinical manifestations of low glucose levels are nonspecific but can range
from mild (subtle impairment) to severe and life-threatening (coma, death).
Because glucose is critical for proper brain function, low levels manifest in
the brain first.
- Headache
- Depression, anxiety
- Palpitations
- Bizarre behavior, mental confusion
- Blurred vision, vertigo
- Excessive sweating
- Tremulousness, incoordination
- Slurred speech
- Seizures (common in children but rare in adults)
- Fatigue
- Coma
- Irritability
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Differential
Diagnosis |
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- Diabetes
- Depression
- Premenstrual syndrome and menopause
- Central nervous system tumors or abnormalities
- Psychiatric disturbances
- Dumping syndrome
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Diagnosis |
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Physical Examination |
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Hypoglycemia is most often suspected on the basis of the history or the
presenting symptoms which may include irritability, confusion, tremulousness,
diaphoresis, and tachycardia. Screening laboratory tests are essential. The
diagnosis of hypoglycemia is based on Whipple's triad: symptoms of hypoglycemia,
low plasma glucose concentrations, relief of symptoms when normal plasma glucose
levels are restored. |

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Laboratory Tests |
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- Blood and plasma glucose
- Serum insulin, calcium, phosphate, uric acid, lipids,
creatinine
- Liver tests
- Insulin antibodies
- Plasma and urine
corticosteroids
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Pathology/Pathophysiology |
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- Fasting plasma glucose levels of 60 to 105 mg/dL are
normal.
- Fasting plasma glucose levels of 45 to 60 mg/dL suggest
hypoglycemia.
- Fasting plasma glucose levels less than 45 mg/dL indicate severe
hypoglycemia
- Fasting plasma glucose levels over 140 mg/dL indicate
diabetes.
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Imaging |
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Computed tomography (CT) scans are used to diagnose non-beta cell tumors,
insulinomas, or other tumors that may be responsible for
hypoglycemia. |

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Other Diagnostic
Procedures |
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- Glucose tolerance test (GTT [fasting])
- Glucose-insulin tolerance test (G-ITT)
- Hypoglycemic index (e.g., calculation of the fall in blood glucose 90
minutes before the nadir divided by the value of the nadir; a hypoglycemic index
>O.8 indicates reactive hypoglycemia)
- Symptom assessment
- C-peptide suppression test
- Glucose infusion test
- Measurement of counter-regulatory hormone
concentrations
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Treatment Options |
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Treatment Strategy |
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Fasting hypoglycemia can be a medical emergency because of the adverse
effects of prolonged low blood sugar on the brain, whereas reactive hypoglycemia
is usually self-limited and rarely produces dangerous symptoms. However, it is
imperative to establish the existence of hypoglycemia and to distinguish between
the two hypoglycemic states. Plasma glucose concentrations must be raised to
normal levels as quickly as possible. Clinical improvement should be expected in
less than 10 minutes. If there is no improvement after 15 minutes, the initial
treatment should be repeated. |

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Drug Therapies |
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- Oral administration of glucose if the patient is awake enough to
swallow (10 to 20 g carbohydrate)
- Intravenous administration of glucose for patients unable to swallow
(25 ml of 50% glucose solution)
- Subcutaneous or intramuscular injection of glucagon (1 mg) is an
alternative to the above treatments, but patients must also eat because the
effect of glucagon is short.
- Intravenous mannitol (40 g as a 20% solution over 20 minutes) and
glucocorticoids (dexamethasone, 10 mg) may be used to treat a delayed recovery
(e.g., patient who remains in a coma after glucose levels return to
normal).
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Complementary and Alternative
Therapies |
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Alternative therapies may also be useful in regulating blood sugar in the
short term. |

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Nutrition |
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- Small frequent meals, preferably five to six a day, high in protein
and complex carbohydrates.
- Minimize simple carbohydrates including sugar, refined foods, juices,
and fruit.
- Eliminate caffeine, alcohol, and tobacco.
Some patients with normal lab values may respond well to dietary changes.
Vitamins and minerals essential to normal glucose regulation
include:
- Chromium picolinate—100 to 200 mcg tid with
meals
- Magnesium—200 mg bid to tid
- Vanadyl sulfate—10 to 20 mg/day
- Zinc—15 to 30 mg/day
- B complex—50 to 100 mg/day
- Niacinamide—500 mg/day
- Pyridoxine (B6)—100 mg/day
- Pantothenic acid (B5)—250 mg/day
- Vitamin C—1,000 mg bid to tid
- Vitamin E—400
IU/day
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Herbs |
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Herbs are generally a safe way to strengthen and tone the body's systems. As
with any therapy, it is important to ascertain a diagnosis before pursuing
treatment. Herbs may be used as dried extracts (capsules, powders, teas),
glycerites, or tinctures (alcohol extracts). Unless otherwise indicated, teas
should be made with 1 tsp. herb per cup of hot water. Steep covered 10 to 20
minutes and drink 2 to 4 cups/day. Tinctures may be used singly or in
combination as noted.
- Siberian ginseng (Eleutherococcus senticosus) provides adrenal
support. Use tincture 20 drops bid, or dried extract 100 mg tid for two to three
weeks, with a one week rest before resuming.
- A tincture of equal parts of licorice root (Glycyrrhiza glabra),
gotu kola (Centella asiatica), Siberian ginseng, and ginger root
(Zingiber officinale), 10 to 15 drops tid, may be used in combination to
strengthen the adrenals and alleviate hypoglycemic
symptoms.
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Homeopathy |
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An experienced homeopath should assess individual constitutional types and
severity of disease to select the correct remedy and potency. Constitutional
homeopathy can provide overall support, but the underlying cause must be
addressed. |

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Acupuncture |
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May be beneficial in decreasing stress and increasing coping
skills. |

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Patient Monitoring |
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If a hypoglycemic mechanism is obvious and treatable (or self-limited), then
no further diagnostic workup is necessary. If a hypoglycemic mechanism is not
apparent, further studies are necessary to determine the
cause. |

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Other
Considerations |
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Prevention |
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Diet is one of the most important factors in avoiding hypoglycemic episodes.
The diet of choice for hypoglycemia should be low in simple carbohydrates and
high in protein and complex carbohydrates. Refined and simple sugars, alcohol,
coffee, tobacco, and caffeine-containing soft drinks should be avoided. Avoid
fasting, and favor more frequent smaller meals over fewer larger meals. Regular
moderate exercise may improve glucose metabolism by increasing insulin
sensitivity and glucose tolerance. |

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Complications/Sequelae |
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Untreated postabsorptive hypoglycemia can result in coma, brain damage, or
death. |

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Prognosis |
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Patients with reactive hypoglycemia can expect no long-term ill effects
because there is no underlying pathology. However, the prognosis for patients
with fasting hypoglycemia depends largely on the underlying disease causing the
hypoglycemia, which may be progressive and sometimes fatal. |

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Pregnancy |
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Pregnancy may be a predisposing factor in reactive hypoglycemia and
adult-onset diabetes. |

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References |
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Anderson RA, Polansky MM, Bryden NA, Bhathena SJ, Canary JJ. Effects of
supplemental chromium on patients with symptoms of reactive hypoglycemia.
Metabolism. 1987;36:351-355.
Branch WT Jr. Office Practice of Medicine. 3rd ed. Philadelphia, Pa:
WB Saunders Co; 1994:574-575.
Fauci AS, Braunwald E, Isselbacher KJ, et al., eds. Harrison's Principles
of Internal Medicine. 14th ed. New York, NY: McGraw-Hill;
1998:2069-2071.
Mowry DB. The Scientific Validation of Herbal Medicine. New Canaan,
Conn: Keats Publishing; 1986:25.
Tyler VE. Herbs of Choice: The Therapeutic Use of Phytomedicinals.
Binghamton, NY: Pharmaceutical Products Press; 1994:141.
Wilson JD, Foster DW. Williams Textbook of Endocrinology. 8th ed.
Philadelphia, Pa: WB Saunders Co; 1992:1232-1248.
Wyngaarden JB, Smith LH Jr. Cecil Textbook of Medicine. 17th ed.
Philadelphia, Pa: WB Saunders Co;
1985:1342-1348. |

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Copyright © 2000 Integrative Medicine
Communications This publication contains
information relating to general principles
of medical care that should not in any event be construed as specific
instructions for individual patients. The publisher does not accept any
responsibility for the accuracy of the information or the consequences arising
from the application, use, or misuse of any of the information contained herein,
including any injury and/or damage to any person or property as a matter of
product liability, negligence, or otherwise. No warranty, expressed or implied,
is made in regard to the contents of this material. No claims or endorsements
are made for any drugs or compounds currently marketed or in investigative use.
The reader is advised to check product information (including package inserts)
for changes and new information regarding dosage, precautions, warnings,
interactions, and contraindications before administering any drug, herb, or
supplement discussed herein. | |