Penitrem A is an indole-diterpenoid neurotoxic alkaloid produced by *Penicillium* species. As a selective BK channel antagonist, it exhibits antiproliferative and anti-invasive activities against various malignancies, and stimulates the spontaneous release of endogenous glutamate, GABA, and aspartate from cortical synaptosomes. It is commonly used to induce tremor models in animals.