They're being called the next OxyContin, and law enforcement officials and activists on the South Shore say the highly potent prescription painkillers being developed could unleash a similar wave of abuse, overdoses and crime.

Several drug companies are developing painkillers containing pure hydrocodone, a narcotic that is a main ingredient in drugs like Vicodin, without combining it with a non-addictive medication like acetaminophen.

None of the new, purer medications has received federal approval, but they've already sparked concern from officials and advocates in South Shore communities already battling abuse of opiates and opioids like OxyContin, hydrocodone and heroin.

"The problem is once they approve them, it's almost impossible to stop it," said Peter Thompson, a Braintree resident whose son Ryan started abusing OxyContin as a teenager and died of a heroin overdose in 2010. "I guarantee it'll snowball. It'll be the same situation" as OxyContin.

The Associated Press reported in December that four pharmaceutical companies are developing painkillers containing pure hydrocodone, which would contain up to 10 times the amount of the highly addictive drug as medications like Vicodin.

A spokeswoman for the federal Food and Drug Administration said the agency does not comment on applications it has received from drug companies or confirm whether it has received them.

On its website, San Diego-based Zogenix said its hydrocodone drug, called Zohydro, would avoid the risk of liver damage associated with long-term use of acetaminophen and that the company planned this year to seek approval to market the product.

A spokeswoman for the company did not return a call seeking comment.

OxyContin was introduced in 1995 as a powerful painkiller to treat patients suffering from severe pain. But illicit users quickly found ways to override the drug's time-release mechanism by crushing the pills into powder and and snorting or injecting it.

Now police in communities like Quincy and Weymouth say they routinely come across people dealing and using prescription painkillers, and that users often end up shifting to heroin, which is cheaper.

Arlene Goldstein, a program coordinator at Impact Quincy, said the new hydrocodone-containing drugs could attract users looking for a new high.

"It'll be no different than OxyContin, but it will be in demand because it's supply and demand," she said. "It's the next new thing. It's like the newest TV show or the newest car."

She said the potency would pose a danger to users accustomed to weaker drugs.