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Drive is a battle enhancement drug, often used by Gebler.
Drive enhances the senses, reaction time and Ether connectivity of the user to some degree, but can't enhance them beyond their innate potential. A standard soldier without Ether abilities can't gain them by taking Drive, and hypothetically, anything you can do under the effect of Drive is something you could eventually grow into.
All graduates of the Jugend military school in Solaris are required to take Drive before their graduation. Students who refuse, like Elly, will be caught and forced to take the drug regardless.
Repeated use of Drive can have negative effects. These are never witnessed, but stated by members of Elly's squad when Vance takes too much.
In the case of someone with high Ether potential, Drive can be a quick way to make a pilot capable of using AERODS without any training, but isn't required.
In the case of Elly specifically, Drive caused an averse reaction with her powers as the Antitype. This violent awakening killed a number of Solaris soldiers and injured many more, and was in no way within the standard parameters of what Drive can induce or cause.