A prescription for any other use, such as weight loss, would be considered “off-label. ”[6] X Research source

The most easily available forms of clenbuterol are formulated for use in livestock. However, some websites illegally sell prescription clenbuterol made for human use.

Let your doctor know if you are taking any other medications, since they could interact with clenbuterol. [13] X Research source

Severe side effects and overdoses are common in people taking clenbuterol at the high doses needed for weight loss or muscle gain. [19] X Research source Be very cautious if you plan to use clenbuterol this way.

Once you’ve taken clenbuterol, it stays in your body for up to 39 hours. For this reason, you can continue to experience side effects for a long time after taking it.