This is another form of DXM that is time-released. It basically has a edible plastic around some of the DXM. This is used in some cough medicines, so when some of the DXM has worn off, then some more will kick in. This is usually not the preferred type of DXM to use recreationally, because it usually takes longer for it to kick in, and it sometimes is not as strong.

While this method is not necessarily a true "extraction" by definition, it does remove everything in the Delsym without requiring any chemicals (except water), resulting in near pure DXM Polistirex.

The method is simple. Take a liquid container (a bottle ranging from 500mL to 2L is sufficient), and pour in the entire bottle of Delsym. Then, add roughly 1.5 times an equivelant amount of water as there is Delsym (for example, if you add 100mL of Delsym, add 150mL of water, yielding 250mL of liquid).

Seal the bottle tightly, and shake vigorously for a minute or so, until everything in the bottle has mixed. Then, put the bottle in a dark place, to settle for at least two to three hours minimum. You should begin to notice after the first few minutes that a fine "sand" is falling to the bottom - this is the DXM Polistirex, which is insoluable with water (and why they tell you to "shake well before using" on the Delsym bottle).

After all of the DXM has settled, you can simply drain off the excess water, by pouring it out (although this may cause the sand to mix with the liquid again), or by cutting a small incision with a knife in the side of the bottle.

The remaining "sand" can be dried (just let the excess liquid evaporate) for whatever reason, or you can just use the wet DXM Polistirex as-is. Note that this method does not remove any of the time-release plastic coating, as is discussed in the next section.

Some people, when using Deslym, will attempt to dissolve some of the plastic coating surrounding the DXM (see this thread for more information), in an attempt to get some dextromethorphan citrate. This partially decreases the time released aspect of the Delsym, resulting in a faster comeup and higher trip intensity, at the expense of the trip's length.

A conversion is usually performed using something highly acidic, such as lime juime, to melt away some of the Polisterex coating on the DXM. The effectiveness of this method is still disputed, though, as many believe that the acidity of citrus fruits (e.g. lemons, limes) is not strong enough to react with the plastic coating.