ATC (Anatomical Therapeutic Chemical) classification is a system for classifying drugs based on their therapeutic and pharmacological properties. It was developed by the World Health Organization (WHO) and is widely used in healthcare, pharmacovigilance, and drug utilization research.
The ATC system is based on five levels of classification:
Anatomical main group (1st level): This level is based on the organ or system on which the drug acts, such as alimentary tract and metabolism, cardiovascular system, or nervous system.
Therapeutic main group (2nd level): This level is based on the therapeutic indication or pharmacological action of the drug, such as anti-infectives, antineoplastics, or psycholeptics.
Pharmacological/therapeutic subgroup (3rd level): This level is based on the pharmacological or therapeutic subgroups of the drugs, such as antibiotics, antihypertensives, or antidepressants.
Chemical subgroup (4th level): This level is based on the chemical structure of the drugs, such as penicillins, sulfonamides, or opioids.
Chemical substance (5th level): This level is based on the specific chemical substance or drug, such as amoxicillin, furosemide, or paracetamol.
The ATC classification system is used for a variety of purposes, including drug utilization research, pharmacovigilance, and drug regulation. It allows for the comparison of drug use and the monitoring of drug safety across different populations and countries.