'Unbelievable': US couple fighting to change energy drink laws after son's death

The heartbroken parents of a teenager who died from a caffeine-induced cardiac event are fighting to raise the age limit to buy energy drinks.

South Carolina couple Sean and Heidi Cripe received the phone call all parents dread in 2017, when they were informed that their son was dead.

A coroner's report found that Davis had most likely died from arrhythmia, a problem with the rate or rhythm of the heartbeat.

The Cripes claim Davis had "chugged" an energy drink, a coffee and a soft drink within a two-hour period, which led to his death.

They shared their story to an energy drink awareness Facebook page, saying their loss had "shattered" their lives.

"It's still unbelievable to me that it happened and everyday I wake-up hoping this nightmare is over," they wrote.

"I'm telling you and we are proof that it can happen at anytime to anyone. And the problem is you are fine, until you aren't fine and then it's too late. There are extreme, dangerous amounts of caffeine in these drinks."

Now they are fighting to change the law to prevent the  sale of energy drinks to teenagers under the age of 18 in South Carolina.

A proposed Bill went to a sub-committee, where medical staff testified that Davis could not have died purely from a caffeine overdose.

"Fatal caffeine overdose from energy drink ingestion is impossible," Dr Ashley Roberts told the sub-committee.

"You need to make sure everything else is okay," added emergency physician and medical toxicologist Dr Donna Seger.

Despite this, the sub-committee passed the Bill on Friday (local time), and it will now go to a full committtee. The Cripes have vowed to keep fighting until it passes.

"It'll be huge, not only for our son Davis but knowing that here on out other kids will be protected," Heidi Cripe told NBC.