Dosage

• According to the Mayo Clinic website, the correct DHEA dosage can range from 25 to 500 milligrams per day.
  
  

Side Effects

• DHEA side effects normally don't occur with DHEA in pill form, but can include feeling tired, headaches, irregular heart rhythm, and nasal problems. Women can have changes with their periods and emotions.
  
  

Hormonal Effects

• Other negative effects of DHEA can include hormonal issues, since DHEA is a hormone. Women may develop male traits including facial hair, voice deepening, and weight gain. Likewise, men may grow more aggressive, have an increase in breast size, or a blood pressure increase.
  
  

Allergies

• It is possible to have an allergic reaction to DHEA as well. If you have an allergy to DHEA, you should not take it at all.
  
  

Cancer

• It is possible, but not proven either way, that another negative effect of DHEA is its potential to cause prostrate, ovarian, and breast cancer.