This refers a physiological and neurobiological state in which repeated exposure to a substance leads to reduced responsiveness, requiring increasingly higher doses to achieve the same desired effect that was previously produced with a lower amount.
Tolerance reflects the body’s adaptation to the presence of a drug, often through changes in brain chemistry and receptor activity. This process can develop gradually with ongoing use and contributes to the risk of dependence or overdose if the dosage continues to escalate.
Sources: UPenn; SAMHSA_NCBI; ProjectKnow; Gosnold; Recovery Research Institute; UNODC