Methylphenidate (Ritalin®)

Boosting Brain Power: Methylphenidate, also known by the brand name Ritalin, is particularly effective at improving concentration. For this reason, it is also prescribed to children with ADHD. (Photo: iStock.com/agsandrew)

Definition

Methylphenidate (Fig. 1) is the active ingredient in the medications Ritalin® and Medikinet®. According to the Narcotics Ordinance, methylphenidate is a prescription-only active ingredient. 

Significance as a Doping Substance

According to the doping rules of the IOC, WADA, and national and international sports federations, methylphenidate belongs to the group of stimulants and is therefore prohibited in competition. In 2000, a total of only 3 positive doping test results involving Ritalin were reported worldwide. In 2012, there were 47 positive test results.  

Effects

Methylphenidate is a psychostimulant. Like amphetamine, it has a phenylethylamine structure (Fig. 1). The effects demonstrated in animal studies are, like those of amphetamine, indirect, involving the release of norepinephrine from intraneuronal stores and the inhibition of norepinephrine reuptake into the storing neurons.
 

This indirect sympathomimetic effect can lead to an increase in blood pressure and an acceleration of the heart rate. The centrally stimulating effects include improved concentration, as well as increased performance and decision-making capacity. Suppression of fatigue and physical exhaustion can, if misused, lead to a misjudgment of one’s own performance capacity. This is associated with a breakdown of physiological systems. In extreme situations and in cases of overdose, this can lead to death. 

Medical use: Hyperkinetic behavioral disorders (ADHD, Attention-Deficit/Hyperactivity Disorder) in children as part of a comprehensive therapeutic strategy, and for compulsive daytime sleep attacks (narcolepsy), also as part of a comprehensive therapeutic strategy.

However, there are many critical opinions regarding the use of methylphenidate in children with hyperkinetic behavioral disorders.

The fact that the use of methylphenidate, particularly in children, should be approached with caution is also described in the relevant prescribing information for the medications Ritalin® and Medikinet®. The following excerpt addresses this: Ritalin® is not indicated in all cases of hyperkinetic behavioral disorders, and its use should only be considered based on a complete medical history and evaluation of the child.

The decision to prescribe Ritalin® should be based on the physician’s assessment of the chronicity and severity of the symptoms in relation to the child’s age. Prescription should not be based solely on individual behavioral characteristics. If the symptoms are associated with acute stress reactions, Ritalin® is generally not indicated.

Side Effects

Insomnia, loss of appetite, and stomach upset;

In children with hyperkinetic behavioral disorders, the following side effects have been observed: overexcitability, fatigue, sadness,
anxiety, tearfulness, headaches, dizziness, weight loss, dry mouth, diarrhea, and constipation; in isolated cases, psychotic reactions;

In adults with narcolepsy: headaches, difficulty concentrating, sensitivity to noise, dry mouth, palpitations, palpitations, ventricular arrhythmias, changes (usually an increase) in blood pressure, and sweating; restlessness, hyperexcitability, aggressiveness, delusions of persecution, anxiety, inflammation of the oral mucosa, and hypersensitivity reactions may occasionally occur; in isolated cases: inflammation or occlusion of cerebral vessels.

Methylphenidate may increase the risk of seizures. Sudden discontinuation may lead to rebound phenomena such as increased need for sleep, food cravings, mood swings, depression, psychotic reactions, and circulatory disturbances.

Further information

Study on detection times of Ritalin® 

 

Fig. 1 Structural formula of methylphenidate