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Clenbuterol hydrochloride is used in many parts of the world for the treatment of chronic asthmatic disorders. It is a beta-2 agonist, with properties which are somewhat similar to adrenaline. It acts on beta 2 receptors and is a CNS irritant.

It is a colorless microcrystalline powder which is very soluble in water, methanol and ethanol. On the other hand, it is hardly soluble in chloroform, and in benzenes it is not soluble at all.

Bodybuilders discovered Clenbuterol Hydrochloride in itself because of thermogenesis, mild build-up properties (slight increase in strength) and because of its anticatabolism. Users put their dosages together depending on desired results, but somewhere between 2-8 tablets per day is most common. For loss of body fat it appears to remain effective for 3-6 weeks. During this period, many users observe a slightly elevated body temperature. Furthermore, during the intake of Clenbuterol, the calories are to be better utilized, so the less is converted into body fat. Therefore, Clenbuterol hydrochloride is already something like must for competition preparation. As I said, the thermogenesis leaves after about 3-6 weeks and at this point you should take a break of at least two weeks. Increasing the dosage would not bring any advantage.

Clenbuterol appears to be effective for a short period of about 3-4 weeks. However, the anabolic effect is low, because unlike with farm animals which are given clenbuterol to build up mass in humans the responsible beta 3 receptors are hardly to none at all.

The actual reason for many bodybuilders to take clenbuterol hydrochloride is the anticatabolic effect, i.e.. It reduces the protein synthesis from the muscle, thus resulting in a preservation and, ultimately, an increase of the muscle cells. This anticatabolic effect is also very effective after counteracting the catabolic phase, which is caused by a cortisone excess and reduced endogenous testosterone production.

Side effects:

Tremor, nervousness, dizziness, nausea, heartburn, disturbances of the kidneys and the urogenital tract

These side effects often disappear or diminish after about 7-14 days when the user is used to the medicine.

Application / dosage:

Oral, In Bodybuilder circles are cures over 4-6 weeks with a dosage between 4-6 tablets à 0.02mg clenbuterol known.

The dosage information given here is not intended as a dosage recommendation or medical advice. These are statements by bodybuilders who have used or used these active ingredients. The dosages should never be regarded as generally valid. If you are using the idea of using steroids or similar, ask a doctor or pharmacist.

Black market price / availability:

There are: “Spiropent mite” with 10mcg of clenbuterol, and spiropent with 20mcg of clenbuterol in tablet form.

The usual pack sizes are 20, 50 or 100 tablets.
There are also spiropent drops, and spiropent juice, but this is less spread than the tablet form.

The black market price for 50 tablets Spiropent with 20mcg clenbuterol is about 20 – 30 euros. As a prescription drug, prescription 100 tablets for about 36 euros to get.


There are counterfeits of clenbuterol hydrochloride, but they are rather rare and most known are found in bottles or doses with loose tablets.


Clenbuterol hydrochloride, Clenbuterolum

Trade name / manufacturer:

Ventipulmin / Boehringer Ingelheim Vetmedica (horse medicament)
Siropent / Boehringer Ingelheim Pharma GmbH & Co. KG
Contraspasmin, Contraspasmina / Europharma Spain
Clenasma / Biomedica Foscama, Italy

Chemical information: 

Clenbuterol: 4-Amino-3,5-dichloro-alpha – [[(1,1-dimethylethyl) amino] methyl] benzenemethanolClenbuterol - Molekularformel

Molecular formula: C12H18Cl2N2O
Molecular weight: 277,190 g / mol
Monoisotopic mass: 276.079620 Da



Clenbuterol hydrochloride: 1- (4-Amino-3,5-dichlorophenyl) -2-tert-butyl-aminoethanol-HClClenbuterol Hydrochlorid - Molekularformel

Molecular formula: C12H19Cl3N2O
Molecular weight: 313.650 g / mol
Monoisotopic mass: 312.056305 Da