In rats, injection of LSD-25 produces autonomic effects including profuse salivation, urination, and defecation. Within minutes, the animals show initial hyperactivity followed by leg flexion and abdomen touching the floor, sometimes remaining motionless for long periods if undisturbed. For rats trained to climb a rope for food, climbing times increased with higher doses, and at the drug's peak effect some rats did not climb at all.
Injection of LSD-25 suppresses food intake in rats, and this effect depends on the dose given. Over ten daily injections, food intake remained suppressed each day, indicating that complete tolerance did not develop. These results suggest caution when interpreting behavioral effects of LSD-25 in experiments where behavior relies on food reinforcement.