Precautions

If caffeine is administered in a kola preparation, kola should always be obtained from a reputable source that observes stringent quality control procedures and industry-accepted good manufacturing practices. Consumers should look for the designations "U.S.P." (U.S. Pharmacopeia) or "NF" (National Formulary) on kola nut labeling. Herbal preparations prepared under USP or NF guidelines meet nationally recognized strength, quality, purity, packaging, and labeling standards as recommended by the United States Food and Drug Administration (FDA).

CAFFEINE CONTENT OF COMMON DIETARY AND MEDICINAL SOURCES
Source	Standard amount in milligrams (mg)
Bottled beverages (12 oz)
Red bull	115.5
Jolt	72
Mountain Dew	55
Diet Coke	45
Dr. Pepper	41
Coca Cola Classic	34
Coffee (8 oz)
Brewed	80–135
Instant	65–100
Decaf brew	3–4
Tea (8 oz)
Iced	47
Brewed	40–60
Instant	30
Green	15
Chocolate
Hot cocoa (8 oz)	14
Chocolate milk (6 oz)	4
Chocolate bar (1 oz)	3–6
Medications (per tablet)
Vivarin	200
No-Doz	100
Midol, Maximum Strength	65
Anacin	32
Dristan	30

Avoid taking too much caffeine when it is being taken as an over-the-counter drug. Consider how much caffeine is being taken in from coffee, tea, chocolate, soft drinks, and other foods that contain caffeine. Check with a pharmacist or healthcare professional to find out how much caffeine is safe to use.

Caffeine cannot replace sleep and should not be used regularly to stay awake as the drug can lead to more serious sleep disorders, like insomnia.

People who use large amounts of caffeine over long periods build up a tolerance to it. When that happens, they have to use more and more caffeine to get the same effects. Heavy caffeine use can also lead to dependence. If an individual stops using caffeine abruptly, withdrawal symptoms may occur, including headache, fatigue, drowsiness, yawning, irritability, restlessness, vomiting, or runny nose. These symptoms can go on for as long as a week. In addition, caffeine dependence is not confined to the adult population. A study published in 2002 found that American teenagers have a high rate of caffeine dependence, partly because they consume large amounts of carbonated beverages that contain caffeine.

If taken too close to bedtime, caffeine can interfere with sleep. Even if it does not prevent a person from falling asleep, it may disturb sleep during the night.

The notion that caffeine helps people sober up after drinking too much alcohol is a myth. In fact, using caffeine and alcohol together is not a good idea. The combination can lead to an upset stomach, nausea, and vomiting.

Older people may be more sensitive to caffeine and thus more likely to have certain side effects, such as irritability, nervousness, anxiety, and sleep problems. Recent findings also suggest that people with insulin-dependent diabetes should monitor their caffeine intake. One study published in 2002 found that caffeine appears to decrease insulin sensitivity by about 15%

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