Starting Sunday, California consumers hoping to purchase products containing dextromethorphan-commonly found in Robitussin-DM, Mucinex-DM, and Nyquil-will have to show proof that they are over 18 years of age.

The change is the result of a new California law that aims to curb abuse of the over-the-counter (OTC) cough-suppressant medication that is being abused by some consumers to achieve hallucinogenic effects known as "robotripping" and "dexing".  Some surveys estimate that 1-in-10 teenagers have abused the drug.

While generally safe when taken as directed, dextromethorphan can cause liver damage, seizures and even death when taken in incorrect dosages.

Supporters say that the legislation is necessary to combat the dramatic increase-and abuse-of the drug during the last decade. Ilene Anderson, senior toxicologist at the California poison control system, says that the drug is easier to abuse because it is easily available and its OTC status lacks the stigma associated with harder, illicit drugs.

Retail clerks found to violate the law will generally be subject to fines up to $250 per infraction unless it can be proven that they are a part of a conspiracy to sell the drug to minors.

• (San Francisco Chronicle)