How Long do Drugs Stay in Your System?

Drugs are synthetic products which can be used as medicines or narcotics. They are of different types and are differentiated on the basis of their effect on human beings. For e.g., certain drugs and medications are classified as depressants, while some others are stimulants. Prescription drugs are taken for medicinal purposes to overcome depression or physical or psychological disorders. However, certain drugs, mostly, narcotics, are consumed illegally and are termed as drugs of abuse.

As the abuse of prescription drugs reaches epidemic levels in the U.S., prompting a corresponding hike in drugged-driving incidents, the window of time that drugs can be detected in chemical testing can be critical information for both law enforcement and defendants in any resulting court proceedings.

Drug detection factors

The length of time that a drug is detectable in the system depends on a variety of factors, including:

• the type of test
• dose
• tolerance
• potency
• metabolism
• the existence of medical conditions

Drug detection times

Please use these figures as a guide only:

• Alcohol: 3-5 days in urine, 10-12 hours in blood
• Amphetamines: 1-3 days in urine and around 12 hours in blood
• Barbiturates: 2-4 days in urine and 1-2 days in blood
• Benzodiazepines: 3-6 weeks in urine and 2-3 days in blood
• Cannabis: 7-30 days in urine and up to 2 weeks in blood
• Cocaine: 3-4 days in urine and 1-2 days in blood
• Codeine: 1 day in urine and up to 12 hours in blood
• Heroin: 3-4 days in urine and up to 12 hours in blood
• LSD: 1-3 days in urine and up to 2-3 hours in blood
• MDMA (ecstasy): 3-4 days in urine and 1-2 days in blood
• Methamphetamine (crystal meth): 3-6 days in urine and 24 - 72 hours in blood
• Methadone: 3-4 days in urine and 24-36 hours in blood
• Morphine: 2-3 days in urine and 6-8 hours in blood

Drug detection in hair

Drugs or their metabolites may be detectable in hair. Hair grows at a rate of approximately 1cm per month so depending on the length of hair it may be possible to determine drug use over recent months.

Too Many Variables

The problem is that an exact timetable for how long drugs remain detectable in urine, blood, and saliva tests is almost impossible to determine, due to the many factors that can affect how an individual's body processes or metabolizes drugs.

Drug detection times can be affected by each person's metabolic rate, which can vary widely. Metabolic rates, in turn, can be affected by the person's age and certain health conditions. The higher the metabolic rate, the shorter the time a drug can be detected in the body.

Hydration, Body Mass

Hydration levels, body mass, physical activity and drug tolerance can also affect how long drugs will be detectable. Drug detection times can be much longer for people with increased fatty tissues, because of some drugs, or their metabolites, tend to accumulate in those tissues.

On the other hand, if someone has built up a tolerance to a drug, the length of time it can be detected in the system can become very short, because it tends to metabolize more quickly.

Frequency and Amount of Use

Another key factor in drug detection time is the amount and frequency of the drug's use. A one-time use of a drug might be detectable for only a short period of time, whereas heavy or long-time use of drugs can be detected for extended periods. Very frequent drug use can cause concentrations in the system that can be detected for lengthy periods after last use.

Even the acid-base balance in urine can affect detection times in urine tests. The more acidic the urine, the shorter the detection time.

Drug Duration Chart

The duration, any drug stays in the body, varies, and can last for hours to days to even more than a couple of weeks. With the use of modern methods of drug testing, it is even possible to detect whether a person had a drug 2-3 months backs. Drug tests include urine test, blood test and hair test which also help in the diagnosis of the type of drug a person has taken. One also needs to take several other things into consideration like the amount of drug the person has taken, whether the drug was taken orally or injected in the body, the person's age, gender, etc. Secondly, a person's rate of metabolism (or metabolic rate) also plays an important role in determining the duration the drug stays in the body. If a person has a slower metabolic rate, it takes a longer time for drugs to get out from the body.

The frequency at which a certain drug is taken (drug abuse) and the drug tolerance capacity of the person also determine the duration of the drug in the body. Most commonly used drugs like codeine, used to relieve cough and pain, can also stay in the body for more than one day. The following is a chart showing the duration of drugs in the system, in case of prescription as well as drugs of abuse.

Prescription Drugs

Recreational Drugs

As there are severe and even fatal effects of drugs on the body, people are advised not to abuse them. It should also be noted that drugs are more addictive as compared to alcohol or cigarette. However, all the three are equally harmful. If a friend, or a partner is found to suffer from drug abuse, he should be encouraged to go to drug rehabilitation where recovery is possible.

Drug abuse is a sure way to end life as it is addictive and life-threatening. So, it is wise to stay away from it. Take care!

• Sources

  1. American Association for Clinical Chemistry "Drugs of Abuse Testing." Lab Tests Online. Revised 2 January 2013.

  2. American Association for Clinical Chemistry "The World of Forensic Laboratory Testing." Lab Tests Online Revised 7 May 2012.