A far milder form of psychological abuse involves exposing prisoners (intravenously or orally) to "truth serums" or Barbiturates.

Sodium Pentathol: A ultra-short-acting barbiturate that depresses the central nervous system, slows heart rate, and lowers blood pressure. In the relaxed state produced by the drug, subjects are more susceptible to suggestion and are therefore easier to interrogate. The drug does not actually guarantee that prisoners will tell the truth, however. Often, it makes subjects "gabby" without revealing any important information.

Scopolamine: A poisonous alkaloid found in various plants (as jimsonweed) of the nightshade family and used especially as a truth serum or usually with morphine as a sedative in surgery and obstetrics.

Scopolamine was first introduced into medical usage in 1902. When scopolamine is given in lower (non-poisonous) doses, it causes drowsiness and amnesia and sometimes a sense of euphoria (a "high").

Sodium Amytal Sodium amytal is a hypnotic sedative drug that, like hypnosis, is occasionally used with trauma survivors to access repressed or unconscious material, such as feelings and memories, or to aid in diagnosis of possible dissociative identity disorder (DID). The drug is administered via an intravenous (IV) drip, usually in an inpatient setting to monitor the slight risk of medical complications. It is used illegally as a crude way of digging up information.

In 1963 the US Supreme Court said "serum-induced confession" was in effect a form of torture and the practice was ruled unconstitutional.