Links Between Methylphenidate (Ritalin) and Cocaine

Methylphenidate (Ritalin, Concerta) is a stimulant medication widely used to treat people with ADHD (attention deficit hyperactivity disorder), and also used to treat the sleep disorder called narcolepsy. Cocaine is the common name for an addictive, stimulating illegal drug made from the leaves of the South American coca plant. Despite their differing uses and legal status, methylphenidate and cocaine are chemically similar and produce the same basic effects inside the brain. Although proper methylphenidate use does not trigger addiction to the drug, some medical researchers believe that people who use methylphenidate in childhood have higher risks for developing cocaine addictions in adulthood.

Chemical Similarities

Addictive drugs produce their altering effects on the mind and body by hijacking the normal activity of brain chemicals called neurotransmitters, which make coordinated brain function possible by relaying signals between more than 100 billion individual nerve cells called neurons. Cocaine and most other drugs of abuse produce rapid, major increases in the levels of a neurotransmitter called dopamine, which helps produce the basic human experience of pleasure. It is the rapid increase of this pleasure-producing chemical that “hooks” drug users and lays the groundwork for eventual problems with drug addiction.

Some drugs increase dopamine levels by directly increasing dopamine production, while others block a recycling process that normally removes dopamine molecules and breaks them down after they do their job. Cocaine and methylphenidate both increase dopamine by blocking this recycling process; their structural similarity is so great that, in principle, they produce virtually the same dopamine-related effects.

If cocaine and methylphenidate are so chemically similar, why does one of these drugs produce an addictive “high” while the other does not? The answer lies in the dosage levels used in legitimate methylphenidate prescriptions, as well as in the different ways the two drugs enter the body. When doctors issue methylphenidate to their patients, they prescribe dosages that are high enough to produce therapeutic (medically beneficial) results, but not high enough to produce the dependence and addiction problems associated with the use of cocaine and other powerful stimulants. Critically, methylphenidate comes in tablet form, not in inhalable, injectable, and smokable forms like cocaine. The body absorbs and uses these tablets much more slowly than it absorbs and uses the various forms of cocaine; inside the brain, this slower absorption rate translates into a smaller average increase in dopamine levels, and much smaller chances for dependence- or addiction-related issues.

Methylphenidate Can Be Addictive

Methylphenidate can be addictive, just like cocaine or other commonly abused drugs. Typically, addiction-related problems arise when someone abuses his or her own prescription for the drug; obtains the drug through someone else’s prescription; or obtains the drug without access to anyone’s prescription. All of these uses qualify as forms of drug abuse. While people using methylphenidate properly and under a doctor’s guidance receive only low doses of the drug, people abusing methylphenidate have no such controls on their behavior. In these uncontrolled circumstances, some people drastically increase their consumption of the drug and end up taking amounts many times higher than a therapeutic dose. In addition, some people crush methylphenidate tablets and create an injectable, inhalable powder; use of this powder can greatly increase the speed of drug absorption, and therefore trigger much higher increases in dopamine levels. All of these factors contribute to the onset of methylphenidate addiction.

Methylphenidate Use As a Factor in Future Cocaine Use

People who take methylphenidate and other ADHD drugs during childhood commonly stop taking those drugs when they reach adulthood. According to the University of Utah’s Genetic Science Learning Center, some former methylphenidate users unconsciously gravitate toward cocaine use in adulthood because of the similarities between the two drugs. In fact, former methylphenidate users may have a higher rate of cocaine use than people who never received treatment for ADHD. In this context, methylphenidate may act as a “gateway drug” that facilitates future drug use.

However, not all reputable researchers agree with the gateway drug hypothesis. For instance, a 2003 study at Harvard Medical School found that use of methylphenidate and other stimulant drugs can actually reduce an adolescent’s chances of using cocaine or other drugs during adulthood. A separate study conducted at Harvard University in 2008 also concluded that methylphenidate and other stimulants used to treat children with ADHD don’t contribute to adult drug-taking behaviors. However, the researchers who conducted this study did not conclude that ADHD stimulant treatment reduces risks for future drug use.

Scientists often disagree when they study similar subject matter. While these disagreements can frustrate or confuse people who want clear health information, they are an inevitable part of the scientific process, and usually contribute to long-term clarity and consensus on issues of major importance.