Introduction:

Methylphenidate (d,l-threo-methyl-I-phenyl-2-piperidine-acetate hydrochloride) is a central nervous system (CNS) stimulant that has been marketed in the United States since the 1950s.  For many years, Ritalin ® (immediate release (IR) product), was the only brand-name product available.  In recent years, other IR, extended release (ER), and long acting (LA) methylphenidate products have entered the market.  These products are primarily prescribed to children for the treatment of attention deficit hyperactivity disorder (ADHD). 

Domestic and worldwide use of methylphenidate has increased dramatically since 1990.  According to the 2004 United Nations International Narcotic Control Board (INCB) report, the United States is the main consumer of methylphenidate accounting for about 70 percent of the global medical use of methylphenidate.

Licit Use:

Methylphenidate is used almost exclusively for the treatment of ADHD.  There is a considerable body of literature on the short-term efficacy of methylphenidate pharmaco-therapy for the treatment of ADHD.  However, attentional improvement is not diagnostic of ADHD.  There is no diagnostic test that can confirm an ADHD diagnosis.

Recent data suggests that some children may continue to have significant ADHD-symptoms into adulthood.  As a consequence, the prescription of methylphenidate for individuals 18 and older is the most rapidly growing market.  Longer acting products, primarily Concerta®, have gained a significant share of the total methylphenidate market.  The IMS Health National Prescription Audit Plus™ reported 14.8 million methylphenidate prescriptions dispensed in 2008.

Chemistry/Pharmacology:

Methylphenidate is a CNS stimulant and produces a number of effects including appetite suppression, increased alertness and increases in blood pressure, heart rate, respiration, and body temperature.  Almost complete absorption of IR methylphenidate occurs after oral administration with peak plasma levels in about 2 hours.  It is extensively metabolized and about 80% of the dose is excreted in the urine as ritalinic acid.  Only 20% of the administered oral dose is bioavailable due to extensive first-pass metabolism.

Biochemically, methylphenidate enhances the release and blocks the reuptake of dopamine (DA) and norepinephrine (NE) in mammalian brain.  Pharmacologically methylphenidate is most closely related to cocaine.  In human subjects, methylphenidate binds to the same receptor sites as cocaine in the brain and produces effects that are indistinguishable from cocaine.

Illicit Use:

Like other potent stimulants, methylphenidate is abused for its “feel good” stimulant effects.  The occasional abuser may use methylphenidate as a study aid to increase attention and stay awake.  Others may use methylphenidate recreationally and combine it with alcohol or some other depressant to feel more alert or less drunk.  Serious methylphenidate abusers often snort or inject methylphenidate for its intense euphoric effects or to alleviate the severe depression and craving associated with a stimulant withdrawal syndrome.

Monitoring the Future (MTF) is a National Institute on Drug Abuse (NIDA) funded study conducted by the University of Michigan.  In 2008, the MTF survey indicated that 3.4% of 12th grade students, 2.9% of 10th grade students and 1.6% of 8th grade students reported nonmedical use of Ritalin in the past year.

The National Survey on Drug Use and Health (NSDUH) is a database that measures drug use by people living in households.  In 2007, the highest non-medical use of methylphenidate among youth was in the 18-25 year old age group with 4.8% reporting lifetime non-medical use.  It is estimated that 1.61 million people misused methylphenidate in their lifetime, according to the 2007 NSDUH report.

The American Association of Poison Control Centers (AAPCC) report indicates 8,766 methylphenidate case mentions and 6,062 single exposures in 2006.  In 2007, 8,994 case mentions and 6,355 single exposures reported to AAPCC were associated with methylphenidate. Nonmedical use of methylphenidate accounted for 2,192 visits to the emergency department in 2006 according to the Drug Abuse Warning Network (New DAWN ED).

The National Forensic Laboratory Information System (NFLIS) is a database that collects data on analyzed drug seizures from federal, state and local forensic laboratories.  In 2008, the NFLIS reported law enforcement submitted 1,382 exhibits of methylphenidate to state and local labs and 81 exhibits to federal labs to be analyzed.

User Population:

While a wide spectrum of the population has abused methylphenidate products, the primary abusers are individuals less than 25 years of age; who often obtain methylphenidate from a friend or classmate and use this drug as a study aid or to party.

Illicit Distribution:

Unlike other potent stimulants, there is no clandestine production of methylphenidate and diverted pharmaceutical products are the only source for abuse purposes.  Methylphenidate is obtained from fraudulent prescriptions, doctor shopping, pharmacy theft and from friends or associates who have obtained the drug through a prescription. 

Control Status:

Methylphenidate is a Schedule II substance under the Controlled Substances Act.

Comments and additional information are welcomed by the Office of Diversion Control, Drug and Chemical Evaluation Section. Fax 202-353-1263, telephone 202-307-7183, or Email ODE@usdoj.gov.