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Drug Detection Times in Urine

Drug/IdentifierMinimumMaximumCut-Off Level
Marijuana (THC)†2 hoursUp to 40+ days50 ng/ml
Cocaine (COC) †1-4 hours2-4 days300 ng/ml
Methamphetamine (METH) †2-7 hours2-4 days1000 ng/ml
Amphetamines (AMP) †2-7 hours2-4 days1000 ng/ml
Ecstasy (MDMA) †2-7 hours2-4 days500 ng/ml
Opiates (OPI) †2 hours2-3 days2000 ng/ml
Phencyclidine (PCP) †4-6 hours7-14 days25 ng/ml
Benzodiazepines (BZO)2-7 hours1-4 days300 ng/ml
Methadone (MTD)3-8 hours1-3 days300 ng/ml
Barbiturates (BAR)2-4 hours1-3 weeks300 ng/ml
Tricyclic Antidepressants (TCA)8-12 hours2-7 days1000 ng/ml
Oxycodone (OXY)1-3 hours1-2 days100 ng/ml

† The Substance Abuse and Mental Health Services Agency (SAMHSA), has set "cut-off" levels when testing for marijuana, cocaine, methamphetamine, amphetamines, ecstasy, opiates, and PCP. First Check is manufactured to conform to those standards. Screening tests may not detect amounts of drugs in a urine sample that are below the cut-off level. Even though some level of drug may be present in a urine sample, the sample would still be considered Negative Result if the drug level is below the cut-off level.


Dr. Barbara A. Krantz

Chief Medical Officer
Hanley Center


Dr. Barbara Krantz has practiced medicine in South Florida for over twenty-seven years. As Chief Medical Officer at Hanley Center, West Palm Beach, Florida, she draws from a wealth of experience in addiction medicine and family medicine.

Prior to joining Hanley Center in 2001, Dr. Krantz was the Medical Director for the Center for Alcohol and Drug Studies. She had earlier been the Medical Director at Cornerstone, a substance abuse treatment program at Wellington Regional Medical Center, and maintained a private family practice that included pediatrics and geriatrics.

Dr. Krantz has also served as Clinical Assistant Professor of Behavioral Medicine at Nova Southeastern University in North Miami Beach, and in 1999 developed the Inner City Outreach Program and the Medical Mobile Unit of West Palm Beach, the first such project undertaken in Palm Beach County. Dr. Krantz has had institutional affiliations including St. Mary’s and Good Samaritan Hospitals in Palm Beach County. She is Founder and Board President of His Great Commission, Inc., providing free medical screening, outreach and referral, and basic medical care primarily to Caribbean-American and Hispanic residents of Palm Beach County.

Dr. Krantz is a member of numerous medical associations including the American Society of Addiction Medicine. She is widely consulted as an addictionologist and has lectured on the biochemistry of the brain as it relates to addiction, the disease concept of chemical dependency, and signs and symptoms that emergency room physicians can look for in identifying addicted patients. She is currently teaching at the University of Miami School of Medicine at Florida Atlantic University as an assistant professor of Biomedical Sciences, was a mentor at Nova Southeastern University and teaches in the Hanley Center professional program.

Dr. Krantz received a Bachelor of Science degree and was class valedictorian at Manhattanville College in Purchase, New York. At the University of Miami (Florida) she graduated Phi Kappa Phi with a Master of Science degree and was class valedictorian. After studying at Des Moines University, Health Sciences, she served an internship at the Southeastern College of Osteopathic Medicine in North Miami Beach. She completed her family practice residency at Miami’s Jackson Memorial Hospital. In 2006 Dr. Krantz was certified by the Medical Review Officer Certification Council (MROCC) as a Medical Review Officer. Certified MROs evaluate drug and alcohol test results in the workplace.

barb k hanley