Schoolies warning to parents

Authorities are warning parents and older siblings not to give underage school leavers alcohol ahead of celebrations at Rottnest, in the South West and overseas.

Regional WA Commander Murray Smalpage said police would use drug dogs during operations to seize illicit drugs and alcohol from teenagers or older so-called "toolies" who targeted school leavers.

He said the celebrations were an important part of leaving school but urged teenagers to look after each other.

Cdr Smalpage also appealed for leavers' relatives or friends not to provide them with alcohol or drugs.

"We'd hate to see any of our leavers do anything foolish that may have life-altering consequences," he said. "Tragically, police have seen the devastating effects of youth mixed with alcohol and/or other drugs."

Police Commissioner Karl O'Callaghan urged leavers who needed medical treatment to be honest with paramedics.

"The priority is not to go prosecuting people," Mr O'Callaghan said.

"We need to encourage kids to tell paramedics what it is they've taken, so paramedics can treat them properly."

Australian Medical Association WA president Richard Choong urged teenagers to avoid drugs and limit their alcohol, saying excessive use could lead to poor choices.

He also reminded them to practise safe sex, saying cases of chlamydia and other sexually transmitted diseases were rising among young people.

Hepatitis Australia warned about getting tattoos or body piercings because of the risk of blood-borne viruses such as hepatitis C.

Support group Red Frogs Australia, which will have volunteers in the South West, Rottnest and Bali, said school leavers heading to Bali were encouraged not to hire scooters and buy only drinks that were sealed because of the risks of methanol poisoning.

Police said they wanted teenagers to have a good time but would take action if they broke laws and would call parents and guardians at anytime of the day or night.

Leavers' week starts on Monday, November 25.

_With AAP _