Caffeine is a naturally occurring compound found in coffee beans and tea leaves.
Coffee, black and green tea, cocoa, cola soft drinks and energy drinks are some of the common beverages that contain caffeine. It may also be found in chocolate bars, energy bars and some over-the-counter medications, such as cough syrup and slimming tablets. Guarana (a popular additive in energy drinks) is a natural source of caffeine
As a stimulant, caffeine acts on the brain and nervous system. In small doses, it can make you feel refreshed and focused. In large doses, you are likely to feel anxious and have difficulty sleeping.
Like many other drugs, it is possible to build up a tolerance to caffeine, which means you become used to its effects and need to take larger doses to achieve the same results. Over time, you may become physically and psychologically dependent on caffeine to function effectively.
While the average caffeine consumption is around 200mg per day, It is recommended that people not exceed to 500-600mg per day. Consuming more than this can result in adverse overdose symptoms. This of course is affected by body weight, health, and individual sensitivity (Source: https://www.caffeineinformer.com/the-half-life-of-caffeine)
You may want to cut back if you're drinking more than 4 cups of caffeinated coffee a day (or the equivalent) and you're experiencing side effects such as:
Frequent urination or inability to control urination
Doctors primarily prescribe Ritalin for Attention Deficit/Hyperactivity Disorder (ADHD), Narcolepsy and Asthma (because the drugs can open up breathing passages). The drugs can also help aid weight loss, as they can decrease appetite in users
When Ritalin in abused, it can either be injected, snorted or simply be used in pill form without a prescription (often in high dosages)
Ritalin is a central nervous system stimulant. Ritalin (methylphenidate) acts in the brain similarly to a family of key brain neurotransmitters called monoamines, which include norepinephrine and dopamine. Stimulants enhance the effects of these chemicals in the brain. At the most basic level, Ritalin works by increasing the amount of dopamine and norepinephrine in the brain, stimulating attention and motivational circuits that your ability to focus and complete tasks. This action results in improved performance and cognitive enhancement. In people with ADHD, Ritalin helps them focus and remain calm. But because Ritalin can significantly increase levels of dopamine in the brain, more and more people seek it for recreational or performance use. In fact, non-medical use of Ritalin is on the rise. Cognitive enhancement is one of the main reason that college students use Ritalin to study. And the surge in dopamine that comes with non-medical Ritalin use is also one of the reasons take Ritalin to get high. But taking Ritalin for non-medical reasons increase likelihood of Ritalin addiction
Taking high doses of a stimulant can result in an irregular heartbeat, dangerously high body temperatures, and/or the potential for cardiovascular failure or seizures. Taking high doses of some stimulants repeatedly over a short period of time can lead to hostility or feelings of paranoia in some individuals.
Treatment of addiction to prescription stimulants, such as methylphenidate and amphetamines, is based on behavioral therapies proven effective for cocaine and methamphetamine addiction. At this time, there are no proven medications for the treatment of stimulant addiction. Antidepressants, however, may be used to manage the symptoms of depression that can accompany early abstinence from stimulants. Treatment includes the slow decrease of drug's dose and the attempt to treat withdrawal symptoms. This process of detoxification could then be followed by behavioral therapies and contingency management.