Cyclizine is apparently a piperizinr derivative that is active against histamine and muscarinic receptors.
The nausea from MDMA and other MDXX drugs is caused by serotonin activating serotonin receptors in the gut. You need a serotonin antagonist like zofran in order to really stop the nausea.
Depending on your physiology and the amount of MDXX drug you're taking, you have to be careful with zofran because it is a serotonin antagonist and can lead to higher levels of serotonin in the body.