Abuse of which drug type can result in recurring effects long after the drug has been taken?

Hallucinogens are known to cause persistent psychological effects that can continue long after the initial use of the drug. These substances can alter perception, mood, and cognitive processes, leading to experiences such as flashbacks or "hallucinogen persisting perception disorder." This means that individuals may continue to experience visual distortions or other sensory disruptions similar to those felt during the drug's active phase.

The nature of hallucinogens allows them to affect the brain's neurotransmitter systems in ways that may outlast the physical presence of the drug in the body. This capability can lead to a lasting impact on one's mental state and perceptions, sometimes resulting in recurring experiences that can be disorienting or distressing. Understanding this aspect of hallucinogens is crucial, especially in military settings where mental clarity and stability are vital for operational effectiveness.