In people who don't drink coffee, a single cup will cause a notable increase in blood pressure. Caffeine begins to exert its stimulating effects within minutes, reaching maximum concentration in the blood between 15 and 45 minutes after it's taken. Significant amounts remain in the blood for 4 to 6 hours. Medicinal Coffee Charcoal does not, however, depend on caffeine for its effect. Instead, its therapeutic value lies in its ability to absorb liquid and dry out the tissues.
Coffee is believed to have originated in Ethiopia.
It was introduced into Arab countries in the early 15 th century, but did not reach Europe until the 16 th century, appearing first in Constantinople, then spreading westward. London's first coffeehouse opened in 1652. Take caffeine with caution if you have a heart condition, kidney disease, an overactive thyroid, a disposition to convulsions, or a tendency to anxiety or panic attacks. Special Cautions Coffee Charcoal, when taken at customary dosage levels, has no side effects. Coffee in beverage form is a different matter.