from wiki entry on theobromine. note it has therapuetic effects on humans. also note theobromine actually has no bromine in it.
Following its discovery in the late 19th century, theobromine was put to use by 1916, where it was recommended by the publication Principles of Medical Treatment as a treatment for edema (excessive liquid in parts of the body), syphilitic angina attacks, and degenerative angina. The American Journal of Clinical Nutrition notes that theobromine was once used as a treatment for other circulatory problems including arteriosclerosis, certain vascular diseases, angina pectoris, and hypertension.
In modern medicine, theobromine is used as a vasodilator (a blood vessel widener), a diuretic (urination aid), and heart stimulant. In addition, the future use of theobromine in such fields as cancer prevention has been patented.
Theobromine has also been used in birth defect experiments involving mice and rabbits. A decreased fetal weight was noted in rabbits following forced feeding, but not after other administration of theobromine. Birth defects were not seen in rats.
Even without dietary intake, theobromine may occur in the body as it is a product of the human metabolism of caffeine which is metabolised in the liver into 10% theobromine, 4% theophylline, and 80% paraxanthine.
In the liver, theobromine is metabolized into methylxanthine and subsequently into methyluric acid. Important enzymes include CYP1A2 and CYP2E1.
As a methylated xanthine, theobromine is a potent Cyclic adenosine monophosphate (cAMP) phosphodiesterase inhibitor; this means that it helps prevent the enzyme phosphodiesterase from converting the active cAMP to an inactive form. cAMP works as a second messenger in many hormone- and neurotransmitter-controlled metabolic systems, such as the breakdown of glycogen. When the inactivation of cAMP is inhibited by a compound such as theobromine, the effects of the neurotransmitter or hormone which stimulated the production of cAMP are much longer lived. The net result is generally a stimulatory effect.
The amount of theobromine found in chocolate is small enough that it can be safely consumed by humans, but animals that metabolize theobromine more slowly, such as dogs, can succumb to theobromine poisoning from as little as 50 grams of chocolate for a smaller dog and 400 grams for an average-sized dog. The same risk is reported for cats as well, although cats are less likely to ingest sweet food, having no sweet taste receptors. Complications include digestive issues, dehydration, excitability, and a slow heart rate. Later stages of theobromine poisoning include epileptic-like seizures and death. If caught early on, theobromine poisoning is treatable. Although not usual, the effects of theobromine poisoning can become fatal.