Clenbuterol
Clenbuterol is a beta-2 adrenergic agonist originally developed as a bronchodilator for asthma. In bodybuilding, it is used as a powerful thermogenic and fat-burning agent that increases core temperature, metabolic rate, and fat oxidation. It is not technically a steroid but is commonly used in competitive prep stacks.
- Also known as: Clen
- Form: oral
- Half-life: 36–48 hours
- Typical cycle length: 2 weeks on / 2 weeks off
- Typical dose (men): 40–160 mcg/day (pyramid)
- Typical dose (women): 20–120 mcg/day (pyramid)
- PCT required: no
Dosing by experience level
| Level | Dose | Frequency | Notes |
|---|---|---|---|
| Beginner | Start at 20mcg, increase 20mcg every 2 days | Daily | 2 weeks on / 2 weeks off protocol |
| Intermediate | Start at 40mcg, increase to 120mcg | Daily | Pyramid up and back down |
| Female | Start at 20mcg, max 80-100mcg | Daily | Lower doses due to greater sensitivity |
Side effects
- Shaking/tremors
- Insomnia
- Increased heart rate/palpitations
- Sweating
- Anxiety
- Electrolyte depletion (potassium/taurine)
- Cardiac hypertrophy with long-term use
Common stacks
- Anavar
- Winstrol
- Testosterone Propionate
- Trenbolone Acetate
- T3 Cytomel
Important notes
- Not a steroid — beta-2 agonist / thermogenic
- Supplement with taurine and potassium to prevent cramping
- Do NOT use for more than 2 consecutive weeks
- Cardiac risks with long-term high-dose use
- Often stacked with T3 for maximized fat loss