Cita:We don't know what's packed into unregulated drugs, so experts can't say with complete certainty how long your coke or acid will last or what will happen to it when it's "old," whatever that means. But they can tell us this: Amphetamine, amphetamine derivatives (like MDMA), and synthetic molecules are incredibly stable and resistant to degradation, says study author Fernando Caudevilla, aka DoctorX, an illicit drugs expert heavily involved in Energy Control, an international project dedicated to recreational drug use safety.


It's possible that these drugs may undergo chemical changes over time, but your stash will likely just lose potency as the weeks and months tick by, Caudevilla says. Synthetic drugs like acid, coke, and ecstasy, and naturally grown drugs like mushrooms and weed, can retain their potency for months or even years if kept in the right conditions.

"Here's the rule of thumb, with all drugs, no matter how much stability data we have," Sachleben says. "These four things are bad: air, heat, light, and water." These elements are damaging enough to cause even incredibly stable substances, like the ones mentioned above, to lose their potency in as little as a few days or weeks, Caudevilla says.

Other factors can also speed up degradation: Improper drying techniques (for weed or shrooms) and certain cutting agents can weaken the strength of the drug more quickly. In that case, its unofficial shelf life is largely up to whoever manufactured your batch. You can do your part to make your stash last by keeping it in a sealed container, like a pill bottle or airtight baggie, in the fridge, says Sachleben, who now sits on the expert panel at the American Chemistry Society.