A number of alkaloids and alkaloidal derivatives have been gas chromatographed on columns of silicone rubber SE-30. The method has also been applied to alkaloidal extracts of crude drugs. Phenolic alkaloids are readily gas chromatographed as the trimethylsilyl ethers. Alkaloidal salts have been gas chromatographed directly. The salt dissociates in the flash heater and the alkaloid is eluted as the base. Under certain conditions, many alkaloids decompose when subjected to gas chromatography. These decompositions often appear to be catalyzed by the glass wool used on top of the column packing.