Stimulants are drugs can increase heart rate and open up breathing, causing users to feel more alert and energetic. When prescribed and used properly, they can be effective aids in treatment of narcolepsy, attention deficit hyperactivity disorder ( ADHD ), and depression that doesn't respond to other treatments. Commonly abused stimulants include amphetamines such as dextroamphetamine (Dexedrine) and amphetamine and dextroamphetamine (Adderall, Adderall XR), used to treat ADHD. Side effects can include tremors, headache , heart palpitations, panic, hallucinations, and paranoia. Overdosage can be fatal.
Products may contain impurities developed in the production stage due to probably lack of hygiene in illegal drug factories. In addition, the active ingredients and their amounts are most likely to differ from the package label promises.
Furthermore, these products have also revealed traces of medicinal substances and other harmful ingredients previously removed from the market for safety purposes. In the manufacturing may have been used construction industry substances as a substitute for the correct medicinal substances, for example. Illegal substances may cause symptoms such as allergic reactions. 
Although this is a new idea in the United States, it was tested in Europe over 20 years ago. In order to combat the AIDS epidemic that was spreading across Europe, France allowed pharmacies to dispense needles without a prescription and implemented needle exchange programs. In 1996, they began a pilot program of syringe vending machines, similar to a coin-operated vending machine. The first vending machines were placed in Marseille due to its high occurrence of AIDS caused by sharing of needles. The results of their study was published in 1999. They found that when the availability of syringes increased, more and more people began to purchase sterile needles. It also provided a discrete way for people to purchase needles without having to feel embarrassed going into a pharmacy. They theorized that with greater access to sterile needles, they would expect to see a reduction in bloodborne pathogen cases.