what causes low dopamine levels

Many things could cause low dopamine levels. some of them include: 

• Medical conditions: Some medical conditions have been linked to low dopamine levels. 
• Poor diet: Eating a diet that doesn’t contain adequate nutrients for optimal brain health could cause low dopamine levels.
• Substance abuse: Abuse of alcohol and recreational drug use can, in the long term, cause your body to reduce its natural production of dopamine.
• Certain medication: Some medications like antidepressants and antipsychotic drugs work by binding to dopamine receptors. This blocks the natural activity of dopamine in your brain.