Question:
Is it permissible to take performance enhancing supplements?
Answer:
In the Name of Allah, the Most Gracious, the Most Merciful.
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh.

One should consider the law relating to this in whichever country you reside in. From an Islamic perspective, it is not permissible to take performance enhancing drugs.[1]  Commonly referred to as steroids, performance enhancing drugs have serious side effects.

Potential risks and side effects[2] of using steroids include:

Men may develop:

• Prominent breasts
• Baldness
• Shrunken testicles
• Infertility

Women may develop:

• A deeper voice
• An enlarged clitoris
• Increased body hair
• Baldness

Both men and women might experience:

• Severe acne
• Increased risk of tendinitis and tendon rupture
• Liver abnormalities and tumors
• Increased low-density lipoprotein (LDL) cholesterol (the “bad” cholesterol)
• Decreased high-density lipoprotein (HDL) cholesterol (the “good” cholesterol)
• Hypertension
• Heart and circulatory problems
• Suppression of the hypothalamic-pituitary-gonadal axis
• Prostate gland enlargement
• Aggressive behaviours, rage or violence
• Psychiatric disorders, such as depression
• Drug dependence
• Infections or diseases such as HIV or hepatitis if you’re injecting the drugs
• Inhibited growth and development, and risk of future health problems in teenagers

 
And Allah Ta’āla Knows Best