Glitteryll, a synthesis of glitterstim and ryll, was a drug produced on Ryloth that decreased the user's memories. It was created by feeding ryll to the energy spiders that produced glitterstim. Another effect of the drug was to cause the spice spiders to grow to massive sizes.
Jedi Knight Quinlan Vos and his Twi'lek Padawan Aayla Secura were both given glitteryll in a conspiracy led by Pol Secura and Asanté Vos. This was carried out under the instruction of Senator Chom Frey Kaa, who was responsible for the production of the drug.
After the death of Pol Secura and the arrest of Chom Frey Kaa, it was believed that glitteryll production was halted, due to Jedi Vos' destruction of all known spice spiders capable of producing it. However, Nas Ghent was said to have smuggled glitteryll in the years leading up to the Battle of Yavin.