Pyr-T, or N,N-tetra methylene tryptamine, is a lesser-known psychedelic drug. Pyr-T was first synthesized by Alexander Shulgin. In his book TiHKAL (Tryptamines I Have Known and Loved), neither the dosage nor the duration are known. Pyr-T produces few to no effects. Very little data exists about the pharmacological properties, metabolism, and toxicity of pyr-T.