Phencamfamine: uses and side effects of this psychotropic drug

Over the last decades, the pharmaceutical industry has developed and commercialized a multitude of stimulant drugs that, They were originally devised to treat problems such as fatigue and tiredness, appetite suppression or lack of concentration.

However, over time some drugs have generated problems of abuse and dependence, and have been withdrawn or banned in certain areas. This is the case of fencamfamine, a drug with stimulant properties that is currently part of a list of prohibited drugs in sport.

Next we will talk about the properties and clinical uses of fencamfamine, its mechanism of action, adverse reactions and contraindications, as well as its effects on the psychological mechanism of latent inhibition.

• Related article: "Types of psychostimulants (or psychoanalleptics)"

Phencamfamin: description and clinical uses

Fencamfamine is a drug with mild stimulant effects on the central nervous system. It was developed by the German pharmaceutical company Merck in the 1960s as an indicated drug for appetite suppression, although it was later withdrawn due to dependency and abuse issues that provoked. Its effects are approximately half as powerful as those of dextroamphetamine.

Fencamfamine has been used to treat daytime fatigue, poor concentration, and lethargy, and is especially useful in patients with chronic conditions, due to its safety profile favorable. The drug was marketed under the names of "Reactivan" and "Glucoenergan", and in its beginnings it was quite popular in the field of sports, particularly among athletes and runners, as its invigorating effects were in high demand in many teams' locker rooms and athletes.

This stimulant medication has been attributed a significant abuse potential due to its psychoactive effects. reinforcers and its mechanism of action, since it acts on dopamine receptors and the reward. In this sense, one of the best known cases in relation to the abuse of this substance was the one that occurred in the Soccer World Cup 1978, held in Argentina, in which soccer player Willie Johnston tested positive for fencamfamine when he was tested anti-doping.

This substance is still included today in the list of substances prohibited in sport within the category of specific stimulants. Currently, fencamfamine continues to be marketed in some countries and is still prescribed as a stimulant drug in patients with fatigue and asthenia pictures. Furthermore, its therapeutic effects in narcolepsy continue to be investigated.

• You may be interested: "Narcolepsy: types, causes, symptoms, and treatment"

Mechanism of action

Fencamfamine acts as an indirect dopamine agonist drug. The mechanism of action of this drug involves the release of this neurotransmitter through a procedure similar to that caused by amphetamines, although the main mechanism is inhibition of the reuptake of dopamine.

Furthermore, unlike amphetamines, fencamfamine does not inhibit the action of the enzyme monoamine oxidase, which participates in the elimination of dopamine, norepinephrine and serotonin, which allows more neurotransmitters to be available at synapses to exert pharmacological effects on target receptors. In fact, studies have shown that the in vitro profile of fencamfamine is more similar to nomifensine, a drug that inhibits the reuptake of dopamine and norepinephrine, which at d-amphetamine.

In animal research on place preference conditioning (a model used to study the motivational properties of certain psychoactive substances) it has been observed that the fencamfamine produces significant place preference only at a particular dose (around 3.5 mg / kg).

In addition, experiments suggest that this drug could act on dopamine D1 receptors, and also on D1 receptors. opioids, since site preference is blocked by a selective dopamine D1 antagonist (SCH-23390) and by an antagonist of opioids (the naloxone).

Adverse reactions and contraindications

The behavioral effects of stimulants are very similar to each other and include increased blood pressure and respiratory rate, and increased heart rate. Nevertheless, fencamfamin is fairly well tolerated and does not produce significant circulatory effects, although prolonged use can cause dry mouth.

It should be noted that this medicine should not be used if you suffer from heart disease, angina pectoris, heart failure decompensated, glaucoma, hyperexcitability, thyrotoxicosis or while being treated with monoamine oxidase inhibitor drugs (MAOI).

On the other hand, an excessive use of fencamfamine or an overdose can cause symptoms such as the following:

• Agitation
• Dry mouth
• Restlessness
• Dizziness
• Tremors
• Dyspnoea
• Tachycardia
• Disorientation
• Seizures

Effects of fencamfamine on latent inhibition

Latent inhibition is a psychological mechanism that people develop and that allows us to filter stimuli from our environment that we perceive as irrelevant based on our particular experience. This ability to "separate the wheat from the chaff," or in other words, to capture only the information that is actually relevant and necessary in a certain situation greatly facilitates us to function in our day to day.

But not all individuals are capable of inhibiting irrelevant stimuli with the same efficiency. People with low latent inhibition are unable to withdraw from a large number of unnecessary stimuli that produce a volume of information that exceeds their cognitive resources, generating high levels of stress and frustration.

Studies carried out in this regard show that fencamfamine blocks the latent inhibition effect at doses of 3.5 mg / kg. A latent inhibition effect that, according to research, could be mediated by the mesolimbic dopamine system. Which makes sense since, as we have discussed previously, fencamfamine acts by inhibiting the reuptake of dopamine causing increased levels of this neurotransmitter in the nucleus accumbens and the body fluted.

On the other hand, it has been shown that at higher doses (around 7 mg / kg) fencamfamine does not block latent inhibition. And since this drug produces stereotyped behaviors at high doses, it is possible that the unconditioned stereotyped responses generated by these doses interfere with the behavioral processes that occur in the conditioning phase of inhibition latent.

Bibliographic references:

• Aizenstein, M. L., Segal, D. S., & Kuczenski, R. (1990). Repeated amphetamine and fencamfamine: Sensitization and reciprocal cross-sensitization. Neuropsychopharmacology.
• Alves, C. R., Delucia, R., & Silva, M. T. TO. (2002). Effects of fencamfamine on latent inhibition. Progress in Neuro-Psychopharmacology and Biological Psychiatry, 26 (6), 1089-1093.
• Gorenstein, C., DeLucia, R., & Gentil, V. (1988). Psychostimulant effects of fencamfamine in healthy volunteers. Brazilian Journal of Medical and Biological Research, 21 (3), 475-477.