metaprot (aka bemitil)Metaprot (Bemitil, 2-ethylthiobenzimidazole hydrobromide) is a synthetic adaptogen and actoprotector with nootropic, antihypoxic, antioxidant and immunostimulant properties, used to increase mental and physical performance under stressful conditions. “Metaprot” is an abbreviation of “Metabolic protector”.

One of the most important properties of Bemitil, as well as the others actoprotectors, is their ability to enhance the effects of nootropic drugs (including Piracetam), psychostimulant and adaptogens. It also can reduce side effects of antibiotics, immunosuppressants, and tranquilizers.

The drug was developed at the S.M Kirov Military-Medical Academy (Soviet Union) in the 1970s for application in military medicine. Metaprot successfully used during:

  • Afghanistan war, to increase soldier’s performance over long marches, and improve resistance to hypoxia and hot weather which was important for Afghan climate.
  • 1980 Olympic games in Moscow, to prepare the athletes of the national team.
  • Chernobyl catastrophe, earthquakes in Armenia, railway accidents in Bashkiria to enhance the mental and physical performance of the rescue workers.

After 1980, Bemitil began to be used widely in all areas of clinical medicine and sport. Now it is manufactured and sold under following brand names: AntiHot (Biofoodpharm, Ukraine), Metaprot (AnviLab, Russia), Bemitil (Belmedpreparaty, Belarus) and Bemiton (Institute of physical organic chemistry of National Academy of Sciences of Belarus)


Metaprot usage and indications

Here is what Bemitil used for:

  • Enhancing the working performance and speeding up the recovery process, especially under extreme conditions (intense physical activity, hypoxia and heat exhaustion).
  • Correction of asthenic conditions (asthenia is similar to chronic fatigue) of various origins, caused by neurasthenia, somatic diseases, intoxications and surgical interventions.
  • As a part of the complex treatment of traumatic brain injuries, cognitive disorders, meningitis, encephalitis and cerebrovascular disorders.
  • Correction of muscular performance of athletes.
  • Prevention of fatigue during prolonged physical activity.

It can be used by healthy adults exposed to stressful conditions. It’s just what this drug designed for. An important thing to note here, that a healthy person that don’t experience any stress or heavy physical loads, likely won’t get a huge effect, or won’t notice any effect at all. The higher stress that you experience, the higher performance increase you will get.


Mechanism of action

structure of metaprot

Benzimidazole actoprotectors, including Bemitil, is similar to purine bases (adenine and guanine) in its structure. Such chemical structure explains the ability of Metaprot to increase the expression of RNA and proteins. The most active stimulation of protein synthesis was found in the skeletal muscle, brain cells, liver, kidney and small intestine. Administration of Dactinomycin (protein synthesis inhibitor) diminishes the protective effect under both normal and hypoxic conditions.

As a result, the processes of physiological and reparative regeneration and adaptation to the new conditions accelerate. Metaprot improves ATP formation and resynthesis of glucose from lactate and pyruvate, which reducing acidosis, lactacidemia, oxygen debt and lead to fast normalization of performance. Bemitil optimizes hormonal regulation of metabolism and oxygen consumption. It also has antihypoxic and immunostimulant activity, which is manifested in the increase of nonspecific resistance of the organism to various infections.



Here is a study performed on 90 patients with Cerebrasthenia caused by traumatic brain injury of medium severity. “Cerebrasthenia” is a term in Russian medicine, which means asthenia caused by psychoorganic syndrome. This condition characterized by headaches, vertigo, mental dysfunctions and fatigue.

Patients were randomly divided into six groups. The first group received 400mg of Piracetam twice daily. The second group – 250mg of Metaprot twice daily. Third group – 80mg of Pirazidol (Pirlindole) twice daily. The fourth group received a stack of Piracetam and Metaprot. The fifth group received a stack of Pirlindole and Metaprot and the sixth group received placebo. The length of the treatment course was 15 days.

The following tests were performed to estimate the efficiency of therapy:

  • Luscher color test to evaluate the level of mental fatigue, anxiety, and performance.
  • Schulte tables to evaluate the attention and visual perception.
  • Lipid peroxidation blood test.

After the 15-days treatment with Piracetam, 70% of patients noticed the decrease of fatigue, their mood, and night-time sleep improved.

In the Bemitil group, on the 10th day of the treatment, 78% of patients noticed improvements. 11% of patients from that group experienced side effects – irritability, insomnia, sweating and pulse lability.

In the Pirlindole group, 75% of patients noticed an improvement on the 12th day of treatment.

In Bemitil+ Pirlindole group, 94% of the patients experienced a decrease of their symptoms, with an onset of the effects on the 5th day. They also did not experience side effects that Bemitil group has.

In the Metaprot+Piracetam group, the treatment was effective for 88% of the patients, with an onset of effects on the 8th day.

Here are the results of the tests.

metaprot nootropic stack for attention increase

antioxidant effect of metaprot

anxiolytic nootropic effect

overall mental performance

The next trial performed on 40 patients with the asthenic condition, caused by chronic ischemia. They were divided into two groups. The main group in addition to the standard therapy (Piracetam and Vinpocetine) received Metaprot (250mg twice daily, three 5-day courses with two days off between each). The control group received standard nootropics therapy. The treatment length was three weeks.

The following tests were used to evaluate the treatment efficiency:

  • The scale of asthenic conditions.
  • Multidimensional fatigue inventory (MFI-20).
  • Visual Analogue Scale to Evaluate Fatigue Severity (VAS-F).
  • Clinical Global Impression scale (CGI).

A combination of Bemitil with Nootropic therapy was the most efficient. In the main group, three patients experienced nausea as a side effect on the 1st week of the treatment, and one patient experienced same adverse effects on the 2nd week.

Here are the results of the tests.

the effects on chronic fatigue

fatigue severity


Side effects

Here is the list of possible side effects according to the official instruction:

  • Irritability.
  • Anxiety.
  • Headaches.
  • Sleep disturbances.
  • Nausea.
  • Flushed face.

According to the clinical trials, side effects are pretty frequent. They include nausea, irritability, insomnia, and sweating. Usual side effect frequency is about 10%.

Also, I analyzed some user reviews. This substance is pretty popular among bodybuilders and athletes. There are a lot of positive feedbacks, but also a lot of side effects reports. Frequent side effect according to the user reviews is a nasal edema, burning sensation in the nose, mouth, and stomach. Bromantane is better actoprotector at this point.



The dosage suggested by the manufacturer is 250mg twice daily. Individuals with body mass above 180lbs may take 500mg twice daily. For performance increase in extreme conditions, take 500-750mg before work. If necessary, you can take 250mg more after 6-8 hours. Maximum daily dosage should not exceed 1500mg in the first day and 1000mg for others.

To maintain high performance long-term, you can take it for a couple of weeks by 5-days courses with two days off (with the daily dosage of 500mg).

A high-carb diet is suggested while taking Metaprot. To avoid sleep disturbances, do not take it after 6 PM.



Metaprot is a useful substance, but not for everyone. It may be useful for athletes and for those who work in stressful conditions. It also stacks well with nootropics and potentiates their effects. However, Metaprot seems to be not very useful on its own, especially for people who don’t experience any physical stress. Also, the side effects are pretty frequent, if you don’t respond well to Bemitil, the side effects may outweigh the benefits.


  1. Center of biomedical researches of FMBA Russia, under redaction of N.N.Karkischenko and V.V. Uiba “Sketches of the sports pharmacology. Tome 3 – vectors of pharmacological regulation.”
  2. A. N. Lyzikov, E. S. Pitkevich, S. N. Melnik “PROSPECTS FOR CLINICAL APPLICATION
  3. P.D Shabanov “Adaptogens and antihypoxants.”
  4. S.M Logvinenko “Experience in the organization of medical support for combat operations in the Republic of Afghanistan.”
  5. U.A Kniazkina “Evaluation of the anti-asthenic effect of Metaprot drug in the patients with chronic ischemia of the brain.”
  6. Sergiy Oliynyk and Seikwan Oh “The Pharmacology of Actoprotectors: Practical Application for Improvement of Mental and Physical Performance.”
  7. P.D Shabanov “Neuroprotective and antiasthenic properties of Metaprot in the treatment of traumatic brain injury consequences.”