MANILA - Only drug tests conducted by the Philippine Drug Enforcement Agency (PDEA) are "unquestionable," Senate President Vicente Sotto III said Thursday as more presidential and vice presidential aspirants publicize their negative drug test results from various medical facilities.

Drug tests from hospitals and clinics are usually "not reliable" as they only use testing kits that could detect a single substance, said Sotto, who once headed the Philippines' Dangerous Drugs Board.

"Hindi puwede 'yung basta drug testing area. Pupunta ka sa clinic, hindi puwede 'yung ganun. Hindi reliable 'yun," the vice presidential aspirant told reporters in a virtual press conference.

(We cannot settle for just any drug testing area. Going to a random clinic is not an option. That's not reliable.)

"[Sa PDEA] Unquestionable, tunay ang resulta at lahat ng droga naka-target... Hindi nakatuon yun sa isa o dalawa lang," he said.

(At the PDEA, the drug test is unquestionable, the results are legitimate. And it targets all illegal drugs, not just focusing on one or two substances.)

The PDEA's drug testing scheme is "transparent" as "every step of the way is supervised," said Sen. Panfilo Lacson, a former national police chief who is running for president in tandem with Sotto.

The two underwent a voluntary drug test at the PDEA last Monday, days after President Rodrigo Duterte claimed a presidential aspirant was into cocaine. They tested negative.

• Lacson, Sotto show negative drug tests after Duterte says presidential bet taking cocaine

"It's the way to go, maski na walang challenge o walang pinatungkulan ang Pangulo tungkol sa isang kandidato," Lacson said, referring to Duterte's blind item.

(It's the way to go, even though President Duterte did not comment on a particular candidate.)

"Mas mainam na rin talagang to show the way [how to do it]," he said.

(It's better to show the way how to do it.)

• Lacson, Sotto show negative drug tests after Duterte says presidential bet taking cocaine

Sotto said the drug testing process at the PDEA is supervised from the filling up of forms, to the collection and sealing of samples.

"Ayaw nila yung pupunta ka sa toilet, paglabas mo may dala ka nang urine sample," he said.

(They don't allow you to go to the toilet unsupervised and suddenly come out with a urine sample.)

"Pati paglalagay ng sample, ikaw ang maglalagay ng pangalan mo doon, ikaw ang mag si-seal... Pati lahat ng drugs na iniinom mo, mga maintenance mo, kailangan ilista mo," he added.

(You will be the one to label the sample and seal it... You also have to enumerate all the drugs you take, including your maintenance medicine.)

Lacson and Sotto were the first tandem to undergo voluntary drug testing after Duterte's allegation against a presidential aspirant.

Manila Mayor Isko Moreno Domagoso and cardiologist Willie Ong, who are running under Aksyon Demokratiko for president and vice president, respectively, also received a negative drug test result from the PDEA.

• 'PDEA is right testing agency': Isko Moreno, Willie Ong test negative for illegal drug use

Former Sen. Ferdinand "Bongbong" Marcos Jr. and Sen. Manny Pacquiao, who are also vying for the presidency, showed negative drug test results from private health facilities. Marcos' test only covered cocaine use.

• Pacquiao camp says he's been cleared of drug use
• Marcos says he took drug test after Duterte cocaine blind item

Duterte's daughter, Davao City Mayor Sara Duterte-Carpio, a vice presidential aspirant, underwent a drug test in a private clinic.

• Sara Duterte tests negative for illegal drugs after dad's cocaine blind item

It is up to the candidates if they want to redo their tests at the PDEA, Sotto said.

"Ang pinag-uusapan natin, top 2 positions of the land. So kailangan transparent," he said.

(We're talking here about the top 2 positions of the land. So, transparency is a must.)

Drug testing for candidates was supposed to be mandatory under the Dangerous Drugs Act of 2002, said Sotto, who helped pass the law.

"Nilagay namin yung probisyon na yun. Dineklara ng Supreme Court na unconstitutional, kaya naalis," he said.

(We placed the provision. But the Supreme Court declared that unconstitutional, that's why it was removed.)

Sotto said he along with Lacson and former Sen. Gringo Honasan have been undergoing voluntary drug tests before elections in the past.

"Mabuti naman na sumunod yung iba," he said.

(It's good that others followed suit.)

"You lead by example. Kailangan malinis at sigurado sila na hindi ka lumalabag sa batas (People have to be sure that officials are clear and do not violate the law.)."

• Why is cocaine-using candidate still free? Duterte says 'the rich take drugs on yachts, in the air'

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