IC&RC AOD Counselor Practice Test

The diminished physiological response in a person using heroin is the breathing rate. Heroin is an opioid that depresses the central nervous system, leading to a slowing of various bodily functions. This includes a significant reduction in respiratory rate, which can be dangerous and even life-threatening in cases of overdose, as it can lead to hypoxia (insufficient oxygen in the body).

In individuals who use heroin, the respiratory centers in the brain become less responsive to carbon dioxide levels, leading to shallow and slow breathing. This is a critical aspect of opioid intoxication and can manifest as one of the most concerning symptoms, making it crucial for counselors and healthcare providers to monitor respiratory function in patients using this substance.

Other options, while they might be affected by heroin use, do not represent the most immediate and dangerous physiological change that occurs. For instance, while activity levels may decrease due to sedation and lethargy, the breathing rate is specifically a direct and acute effect of the drug that poses immediate health risks.