Crystal Meth is actually an FDA-Approved Prescription Medication in the US

Hello Meth expert here. (Not a user though, studied clandestine production as my chem thesis)

D-Meth is the recreational version, while L-Meth is the medicine approved for use.

If I remember correctly the Levo is about 8 times less potent in activating the CNS than the Dextro so while still "feeling good" it isn't even close to the rush of Dextro.

The racemic mix of both is also less potent due to this reason. (Interestingly its actually less than half potent as D-Meth by itself due to the L-Meth binding more strongly to the receptors blocking the D-Meth)

Some meth history for everyone: Originally meth cooks were making it via Phenylacetone (or P2P as they call it) which creates the racemic mixture and that was the OG "speed". This was actually a powdered drug in its pure form (usually goo like in nature as a street drug due to impurities and absorbing small amounts of water) as Racemic drugs do no crystalize well with each other due to the left and right nature.

Then down the line they worked out they can just directly reduce pseudoephedrine into Meth. The "beauty" of this is that pseudoephedrine is only in the Dextro state and the reduction keeps it that way making pure D-Meth. This is known as crystal meth as it will from large crystals with itself. The product is about 6 - 8 times more euphoric than its predecessor "speed"

And now you know why the term Crystal Meth became such a big thing.

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