Think of it as a new draft notice in the war against drugs. We’ve gotten used to reading about heroin, fentanyl and opioid overdoses. Now there’s a new villain: synthetic cannabinoids.

News reports have emerged indicating that this designer drug is growing in popularity. In concentrated forms it can be as lethal as it is undetectable — and it is proving to be very undetectable.

Synthetic marijuana’s name is misleading. According to the Centers for Disease Control, the chemical substances known collectively as synthetic cannabinoids are made in Asian laboratories and marketed over the Internet. The clear, odorless substance can be liquified and blotted on the pages of a book or letter, even clothing. This intensely concentrated form of “fake weed” can cause serious side effects that are very different from those of marijuana — rapid heart rate, vomiting, agitation, confusion and hallucinations.

Over the course of two days in mid-August, more than 95 people in New Haven, Conn., overdosed on synthetic marijuana, officials said.

As several prison guards in Pennsylvania learned last month, reaction to the drug can be caused simply by contact. About 50 guards and other prison employees were treated for exposure to a mystery substance believed to be synthetic marijuana.

It should raise the level of public alarm to realize that symptoms do not respond to the opioid antidote naloxone.

Another major complicating factor: According to a University of Maryland study published just last month, existing drug tests don’t detect synthetic marijuana. It’s as if the drug doesn’t even exist.

The Maryland study involved urine specimens of 175 Baltimore-area residents with known drug use. The samples were sent to the Armed Forces Medical Examiner System laboratory in Delaware where they were tested for 26 synthetic cannabinoids, 59 designer drugs and 84 other illicit and prescription drugs.

“We were thoroughly amazed that in a study where we thought everyone was having a synthetic cannabinoid-related problem, only one specimen tested positive for synthetic cannabinoids,” said principal investigator Eric Wish, Ph.D., director of the Center for Substance Abuse Research at the University of Maryland, College Park, College of Behavioral & Social Sciences.

That’s a big problem for Pennsylvania’s prison system, which announced Wednesday an extensive overhaul of policies intended to keep the drug out of prisoners’ hands.

The new SCI policies cover mail handling, visits and detection of drones. In the previous month, about 50 staff members in a number of prisons reported symptoms that might have been caused by exposure to toxic chemicals. The state correctional institution at Mercer and the Butler County Prison were among the first detention facilities to report incidents.

Pennsylvania’s 25 state prisons have been on lockdown for a week while officials investigate the spate of illnesses. The cause is suspected to be a clear, odorless substance known as synthetic marijuana that can be concealed in the paper of books and letters.

Inmate mail will be processed outside of the prisons, except correspondence with lawyers.

The state is expanding its detection of drones and use of body scanners. Visiting room staff will be doubled and photos and vending machines won’t be allowed for 90 days.

Disturbing trickle-down repercussions should be anticipated. The urine tests that don’t detect synthetic marijuana are the same tests being used on our school children. They don’t detect this new strain of drug, and when a more sophisticated version is developed that does detect them, it will have a higher price tag.

Do we want to wait until that time to reconsider school anti-drug strategies? Is waiting a practical option?