When you purchase kratom, you need to make sure it is from a legitimate company. If you buy it from an unscrupulous vendor, they may be spiking it with an opioid, synthetic substance, or even alcohol. The result is an unsafe product that could have harmful side effects.
Some states have laws that ban the sale of adulterated kratom. This act, known as the Kratom Consumer Protection Act, defines who can sell kratom and what you should look for when buying it. It also imposes penalties on companies that violate the law.
Kratom has been used for centuries as a sedative, pain reliever, and stimulant. It is naturally harvested in Southeast Asia. It is chewed into a bitter green powder and consumed as a tea. However, it has been known to cause overdoses.
Many kratom products contain high levels of 7-hydroxymitragynine (also called phenethylamine), a chemical that is found in the brain. This drug interacts with the mu opioid receptors and produces sedating and analgesic effects. Therefore, it is recommended that you consult with a medical professional before consuming kratom. Taking it without a doctor's recommendation can be hazardous.
Several kratom products have been seized by the FDA, and in recent years it has been discovered that some of these products have been tainted with other substances. These are usually caused by people blending other substances into kratom. In one case, nine people died in Sweden after they were exposed to Kratom that had been tainted with a potent opioid. I would suggest to read this kratom vendor compilation and comparison from kratom.org: http://kratom.org/vendors/.

Some kratom products may be adulterated with illicit fentanyl, which is a powerful opioid that can be found in a wide variety of street drugs. Illicit fentanyl is 100 times more potent than morphine. As more and more street drugs are laced with it, the risks for overdose have become higher. Consequently, the federal government is attempting to control its use.
Kratom is not currently regulated by the United States Controlled Substances Act, but there are steps being taken by the federal government to curb its use. The FDA has banned imports of kratom-containing supplements as of February 2014. While it is safe to consume kratom on its own, the drug can be dangerous when combined with other substances.
According to the American Kratom Association, kratom is a herbal product that can be used to treat pain and promote energy. It is also considered an herbal remedy for a number of ailments. Because of its medicinal benefits, kratom is gaining popularity.
But despite the popularity of kratom, some companies are still selling tainted or adulterated kratom. One example is Kona Kratom, which makes a tea and capsules. Other kratom manufacturers include Strange Clouds, which has a line of different flavors. And a company called Robitussin is adding nausea-inducing components to its kratom cough syrup.
There is a growing concern that vendors are spiking kratom. That's why the American Kratom Association is working to protect legal kratom consumption in the U.S. They are also trying to stop companies that misbrand their products, or that make unverified safety claims.