Missouri House has passed and sent to the senate a bill cracking down on meth, by requiring p[prescriptions for some cold and allergy medicines that contain pseudoephedrine. The decongestant’s a key ingredient in making methamphetamine. the law, prescriptions would be required for solid tablets that contain the substance. Liquids and gel-caps could still be purchased without a prescription. The state already requires pharmacies to keep pseudoephedrine remedies behind their counters and limits the amount customers can buy at one time.