Jamie Murphy has been released from custody after Bali police confirmed there were no drugs detected in the Perth teenager's blood and urine, or in the white powder found on him in a Kuta nightclub.

Key points: Murphy detained after security guards allegedly found him carrying small sachet of white powder

Murphy detained after security guards allegedly found him carrying small sachet of white powder Police say Murphy is still "under investigation" and has not been charged

Police say Murphy is still "under investigation" and has not been charged Murphy's parents flew to Bali on Wednesday morning, teen expected to head back to Australia "as soon as possible"

Police Chief Inspector Sugeng Priyanto said the powder tested positive for painkillers, caffeine and cough medicine.

Earlier on Wednesday Mr Murphy's lawyer said police forensic tests on the white substance had returned negative results.

Mr Murphy's lawyer said the teenager would leave the city as soon as possible.

The 18-year-old has spent almost two days in custody at a Kuta police station following his arrest after nightclub security guards claim they found white powder in his bum bag on Tuesday.

Police said he admitted buying the material from a dealer on the street in Bali, but footage of his arrest shows the distraught teenager denying the powder belonged to him.

Last year a 26-year-old Australian man was jailed for 12 months for possessing one joint of cannabis, and in 2011 a 14-year-old Australian boy spent two months in detention after he was caught with a small amount of hashish.

This is a popular time of year for recent high school graduate "schoolies" to travel to Bali to celebrate.

Mr Murphy graduated from Ellenbrook Secondary College last year, the school said.

Murphy receiving consular support, Bishop says

On Wednesday, Mr Murphy's parents flew to the Indonesian resort island to see their son.

Brendan and Anna Murphy did not answer questions at Perth Airport, but when asked if there was anything they wanted to say, Brendan Murphy said: "Just that we love our son".

Brendan and Anna Murphy at Perth Airport preparing to fly to Bali. ( ABC News: Briana Shepherd )

Mr Murphy's soccer club, Bayswater City, posted a message of support on their Facebook page.

Mr Murphy's soccer club put the poster on their Facebook page.

"We would like to extend our support to Jamie Murphy and his family on this absolutely tragic situation," the post said.

"We will do whatever we can to help bring Jamie home!

"Anna Murphy would also like to pass on her gratitude to everyone who has contacted the club to offer their help and support."

The club also posted a compilation of pictures of Jaime playing soccer, under a banner, "Bring Jamie Murphy home" on the page.

Australia's Foreign Minister Julie Bishop told Sky News consular staff had contacted the 18-year-old and would meet with him.

Ms Bishop said Mr Murphy's family was receiving consular support in Australia, and reminded travellers that Australians were subject to local laws when they were overseas.