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Clenbuterol for weight loss
Last reviewed: 04.07.2025
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The drug Clenbuterol belongs to the pharmacological group of beta-adrenergic agonists for the treatment of bronchopulmonary diseases. However, the presence of a number of metabolic effects in this drug has given rise to the practice of using Clenbuterol for weight loss, which is not approved by doctors.
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Indications for use
According to the official instructions, Clenbuterol (other trade names – Contraspazmin, Spiropent) has the following indications for use:
- chronic bronchitis;
- bronchial asthma;
- chronic obstructive pulmonary disease (COPD);
- dust bronchitis and pulmonary fibrosis in silicosis;
- pulmonary emphysema;
- pulmonary tuberculosis.
The drug is available in the following forms: tablets of 0.02 mg; syrup (in 100 ml bottles).
Pharmacodynamics
The mechanism of action of Clenbuterol on the bronchi and lungs - relief of spasms, reduction of mucus production, reduction of its viscosity and improvement of excretion - is provided by the active substance - clenbuterol hydrochloride, which is 4-amino-alpha (tert-butyl-amino) methyl-3,5-dichlorobenzyl alcohol. Clenbuterol has the same effect on beta-2-adrenoreceptors as adrenaline and noradrenaline, that is, it excites them. When interacting with the membrane enzyme AC, the concentration of cyclic adenosine monophosphate (cAMP) in cells increases and protein kinases are inactivated. As a result, the transmission of the inflammatory signal of the immune cells of the bronchi and lungs is inhibited and their muscle fibers are relaxed.
But this drug also affects beta-1-adrenergic receptors of the heart and beta-3-adrenergic receptors, which are localized in adipose tissue. Thus, Clenbuterol for weight loss acts by stimulating beta-3-adrenergic receptors, which leads to a metabolic effect - increased heat production and activation of lipolysis. In addition, an anabolic effect of this drug is noted, which is due to a positive effect on protein synthesis. For this reason, in sports medicine, the drug is considered doping and is prohibited.
Pharmacokinetics
After oral administration, Clenbuterol for weight loss is absorbed in the gastrointestinal tract and enters the systemic bloodstream; bioavailability is 89-98%. The half-life lasts more than a day, residual levels of the active substance are detected in the blood 48 hours after a single use.
Clenbuterol is broken down in the liver by gluconation (conjugation with glucuronic acid), and the metabolites are excreted through the kidneys.
How to drink Clenbuterol for weight loss?
You should start taking Clenbuterol for weight loss with a minimum daily dose of 20 mcg (one tablet of 0.02 mg), the maximum daily dose is 120 mcg. For men, the initial dose is 40 mcg (two tablets) per day, the maximum daily dose is 140 mcg.
There are two schemes for taking Clenbuterol for weight loss - "explosive" and regular
According to the first scheme (popular among bodybuilders), the drug is taken for 14 days, starting with a minimum of 20-40 mcg, with an increase in dosage daily or every other day. By the end of the second week, the daily dose should be 100-140 mcg (5-7 tablets). Then a two-week break is taken, after which the intake is resumed with a dose of 100-140 mcg.
The main problem with this method is that the use of beta-adrenergic agonists leads to addiction, and stopping taking the pills slows down the metabolism.
The second scheme is considered the best, which involves a gradual increase in the dose from the initial 20 mcg to 100 mcg over 14-17 days. There is also an option: the minimum dose is taken for four weeks without increasing.
Clenbuterol should not be used for more than 16 weeks in any calendar year.
Overdose of Clenbuterol causes increased side effects: tremor, arrhythmia and increased heart rate, drop in blood pressure, psychoneurological disorders. A significant overdose is fraught with cardiac arrest.
Clenbuterol and Thyroxine for weight loss
Thyroxine (L-thyroxine, Levothyroxine, Euthyrox, Eferox) is a synthetic analogue of thyroid hormones - it is used to compensate for the deficiency of endogenous thyroid hormones in hypothyroidism of various etiologies.
The combined use of Clenbuterol and Thyroxine for weight loss is explained by adherents of drug-induced weight loss by the fact that thyroxine affects metabolism, activating the breakdown of proteins and lipids. See more - Thyroid hormones for weight loss
Increasing the daily dose produces side effects, in particular, decreased appetite and body weight, sleep disturbances, diarrhea and vomiting, tremors, tachycardia, increased sweating, instability, a feeling of restlessness and increased anxiety.
Analogues of Clenbuterol for weight loss: Salbutamol, Ventolin, Isadrin (Bronchodilatin, Neoepinephrine, Neodrenal, Ritodrin, Euspiran, etc.), Terbutaline (Bricanil), Fenoterol (Partusisten), Hexoprenaline.
Doctors' reviews of Clenbuterol for weight loss are clearly negative: the use of drugs not as prescribed can only harm health. Thus, the use of this drug leads to an imbalance of thyroid hormones and the development of secondary hypothyroidism.
Analyzing reviews of those who have lost weight about Clenbuterol for weight loss, we can conclude that the use of this drug leads not only to weight loss (on average 2-3 kg per week), but also to a deterioration in well-being.
Storage conditions: away from sunlight, at room temperature.
Shelf life: 24 months.
Contraindications for use
Contraindications to the use of Clenbuterol are individual hypersensitivity, thyrotoxicosis, cardiac arrhythmia with tachycardia, hypertrophic obstructive cardiomyopathy, acute myocardial infarction.
Use during pregnancy – in the first three months and one month before delivery – is contraindicated.
Side effects
The use of Clenbuterol for weight loss most often causes side effects, manifested by tachycardia, changes in blood pressure towards a decrease, hand tremors, dry mouth, nausea, urticaria. Headaches, insomnia, a state of increased anxiety and nervousness also appear.
Using Clenbuterol for weight loss activates the breakdown of glycogen in the liver (glycogenolysis), which leads to an increase in blood sugar with possible hyperglycemia. In addition, the drug can cause a loss of potassium and a decrease in taurine synthesis, which causes muscle spasms.
The most dangerous side effect of this drug is ventricular hypertrophy.
Interactions with other drugs
Clenbuterol is incompatible with beta-blockers. Simultaneous use with blood sugar lowering agents neutralizes the effect of the latter. Clenbuterol increases the risk of extrasystole when used with cardiac glycosides.
Attention!
To simplify the perception of information, this instruction for use of the drug "Clenbuterol for weight loss" translated and presented in a special form on the basis of the official instructions for medical use of the drug. Before use read the annotation that came directly to medicines.
Description provided for informational purposes and is not a guide to self-healing. The need for this drug, the purpose of the treatment regimen, methods and dose of the drug is determined solely by the attending physician. Self-medication is dangerous for your health.