The risks associated with psychedelic drugs are mostly psychological, not physical. Physically, psilocybin mushrooms are considered one of the least toxic drugs known. Reported symptoms like nausea, increased perspiration, numbing and tremors, can sometimes make psychological symptoms like anxiety, panic attacks, paranoia, and mood swings seem worse. Long-term physical effects directly attributed to the pharmacology of psilocybin are rare, and research suggests they may also be due to latent psychological disorders.