Caffeine is a crystalline alkaloid, which is often bitter, and acts as a stimulant drug. Caffeine is naturally found in leaves, seeds and fruits of some plants. Caffeine is most commonly found in coffee and tea, which are primarily from seeds and leaves (coffee plant and tea bush). Caffeine is also found in chocolates and sodas that also contain naturally occurring caffeine from the natural ingredients found in these beverages and foods. Caffeine is also found in tablets, where it is used as a psychoactive drug.
Caffeine is a potent stimulant of the central nervous system. The presence of caffeine overdose or toxicity leads to the over stimulation of the central nervous system known as caffeine intoxication or commonly, caffeine jitters. The presence of excessive amounts of caffeine may lead to over activity of the central nervous system leading to various symptoms of caffeine overdose.
Overdose of Caffeine
The lethal dose of caffeine is 10 grams per orem or by mouth. The general guide is a dose of 150 mg/kg of caffeine may seem to cause overdose in patients. This may be observed in those taking caffeine tablets. However, an overdose from intravenous caffeine administration may be as little as 3.2 grams.
For coffee drinkers, 80 to 100 cups of coffee is equivalent to the lethal dose of caffeine tablets. Small children who may take 35 mg/kg caffeine may already experience caffeine overdose.
Symptoms of Caffeine Overdose
The presence of caffeine overdose leads to symptoms involving the central nervous system as well as other organs in the body. Symptoms include:
1. Restlessness and irritability
The most common symptoms of caffeine overdose are restlessness or irritability because of rapid firing of nerve impulses in the brain.
There may also be heightened anxiety because of over stimulation.
People may also experience fidgeting. Those who are coffee drinkers may observe trembling and uneasiness when they have already consumed too much coffee in a day.
Caffeine overdose may also lead to excitement. Those who are fond of drinking coffee, soda and eating chocolates may have this symptom as a benefit for ingesting too much of them.
Coffee has been known to delay sleep in times that you need to stay awake during the night. In caffeine overdose, this effect is heightened leading to inability to sleep in 24 hours.
Caffeine also leads to vasodilatation of the blood vessels leading to flushing of the skin.
7. Increased urination
Caffeine is also a potent diuretic. Ingesting too much of it may have increased effects on the kidneys, thus leading to excessive urination.
8. Muscle twitching
Caffeine overdose may also affect the normal impulse transmission in the muscles from the brain. Rapid firing of impulses to the motor cortex may lead to twitching and spasms.
9. Gastrointestinal disturbance
Patients may also suffer from diarrhea as the body’s way of eliminating too much caffeine.
10. Rapid and irregular heart beat
Caffeine is also a cardiac stimulant leading to increased heart rate when caffeine is ingested in excessive amounts. Patients may sometimes experience palpitations.
Presence of very large amounts of caffeine may induce mania in people having bipolar disorder.
People with predisposition to psychiatric problems may also experience hallucinations, delusions and even psychosis with caffeine overdose. Death from caffeine overdose is typically caused by cardiovascular affectation specifically the presence of ventricular fibrillation.
Treatment of Caffeine Overdose
The treatment of caffeine overdose is usually supportive, which provides management for the symptoms of caffeine overdose. These may include administration of beta blockers to reverse the effects of beta adrenergic stimulation, which causes cardiac stimulation. Patients may also be required to undergo gastric lavage with activated charcoal to remove the large amounts of caffeine ingested to prevent absorption in the gut. High serum levels of caffeine may require measures to eliminate the caffeine from the blood rapidly such as hemodialysis, peritoneal dialysis and hemofiltration.