If you drank the same amount with Barbs there's a chance you wont wake up. Just ask Hendrix or Morrison etc etc. That's why they stopped them in the first place and replaced them with Benzo's.
By the way your thinking of the drug Secobarbital better known under it's brand name Seconal. Seconal is a Barbiturate, Methaqualone or Quaalude is a sedative-hypnotic drug which is similar in effect to barbiturates. Seconal was link to a lot of high profile drug overdoses, here is a list of the more well know people to OD on Seconal:
*
Judy Garland was found dead in her bathroom by her husband Mickey Deans on June 22, 1969. The stated exact cause of death by coroner Gavin Thurston was accidental overdose of barbiturates; her blood contained the equivalent of 10 Seconal 100 mg capsules.[2]
*
Brian Epstein, the Beatles' manager, died at his house in London on 27 August 1967. The stated exact cause of death by coroner Gavin Thurston was accidental overdose of barbiturates
*
Tennessee Williams was reported to have died of "acute Seconal intolerance" at the Hotel Elysee in New York City in 1983. Reports at the time indicated he had choked on a bottle cap but later reports indicated the Seconal connection.[3]
*
Jimi Hendrix, guitarist and vocalist, died while at girlfriend's Monika Dannemann flat in London. The coroner Gavin Thurston accepted that he had probably taken nine of his girlfriend's tablets, after which he vomited and choked to death due to the tablets. He gave an open verdict (not enough evidence to say why he took so many tablets). He died September 18, 1970 aged 27.
*
Alan Wilson, vocalist and founding member of Canned Heat, was found dead at age 27 in 1970, from a self-induced overdose of Seconal.[4]
*
Dorothy Kilgallen, an American journalist and television game show panelist, was found dead on November 8, 1965, having apparently succumbed to a fatal combination of alcohol and Seconal, possibly concurrent with a heart attack.
*
Dinah Washington, blues, R&B and jazz singer, was found dead at age 39 in 1963, from a lethal combination of secobarbital and amobarbital.[5]
*
Beverly Kenney (January 29, 1932, Harrison, New Jersey – April 13, 1960, New York City) was an American jazz singer. Kenney committed suicide through a combination of alcohol and Seconal. She was 28.
*
Carole Landis was a popular actress of the 1940s who committed suicide on an overdose of Seconal in her Pacific Palisades, California home on July 5, 1948. She was 29.
*
Lupe Velez was an actress in the 1960's, who inspired Andy Warhol's 'Lupe'. She drowned with her head in the toilet after taking a huge dose of Seconal.
*
Aimee Semple McPherson a Canadian-born evangelist and media celebrity in the 1920s and 1930s was found in a hotel room unconscious on September 26, 1944 after taking Seconal.
*
Leila Pahlavi (27 March 1970 – 10 June 2001) Leila Pahlavi was the youngest daughter of the Late Shah of Iran, Mohammad Reza Pahlavi and his wife Empress Farah. On Sunday 10 June 2001, Leila was found dead in her room in the Leonard Hotel in London just before 19:30 BST by her doctor. She was found to have more than five times the lethal dose of secobarbital in her system, along with a nonlethal amount of cocaine.
*
Charles Boyer 28 August 1899 – 26 August 1978 was a French actor who appeared in more than 80 films between 1920 and 1976. On 26 August 1978, two days after his wife died from cancer, and two days before his own 79th birthday, Boyer committed suicide with an overdose of Seconal while at a friend's home in Scottsdale.
*
Poet Alejandra Pizarnik died in Buenos Aires of a self-induced overdose of Seconal.
*
Singer Phyllis Hyman (July 6, 1949 – June 30, 1995) committed suicide by overdosing on pentobarbital and secobarbital in her New York City apartment.