A new formula for methamphetamine using a two-liter bottle, cold pills and some common household chemicals has made its way to Iowa.

State drug authorities say they’ve seen signs that so-called “shake-and-bake” meth is being produced in Iowa. The method produces small amounts of the addictive drug with only a relatively small number of pills of the decongestant pseudoephedrine — an amount easily obtained under even the toughest anti-meth laws.

The pills are crushed, combined with some common household chemicals and then shaken in the soda bottle. No flame is required — but it can produce powerful explosions and fires.

Iowa drug czar Gary Kendell said the method has shown up in Muscatine and Webster counties. Authorities have found empty plastic bottles lined with the toxic byproduct along some roads.