DoktorABC editorial team
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How long THC stays in the blood depends on various factors. These include the dosage, the frequency of consumption and the individual metabolism. In this article, you will learn how long THC can be detected in the blood and what influences the duration.
In this article you will learn:
- You will find out how long THC stays in the blood.
- You will learn which factors influence the detection time.
- You will receive information about different testing methods.
- You will find answers to frequently asked questions about THC testing.
- You understand why THC can be detected for different lengths of time.
What influences the detectability of THC in the blood?
The detectability of THC in the blood depends on several factors that can vary from individual to individual. The most important influencing factors are the dosage and frequency of consumption, the individual metabolism, the body fat percentage and the method of consumption.
Dosage and frequency of consumption
The higher the dose and the more frequently THC is consumed, the longer it remains detectable in the blood. In occasional users, THC may no longer be detectable after just a few hours or days. In regular or heavy users, however, it may take several days or even weeks for THC to completely disappear from the blood. This is because with frequent consumption, THC accumulates in the body and is broken down more slowly.
Individual metabolism
The metabolism of the user plays a major role in the length of time THC is detectable in the blood. People with a fast metabolism break down THC faster, meaning it is detectable in the blood for a shorter period of time.
Conversely, people with slower metabolisms may retain THC in their blood for longer. Metabolism, in turn, is influenced by several factors, including age, general health, and genetics.
Body fat percentage
THC is fat-soluble and is therefore stored in body fat. People with a higher body fat percentage tend to keep THC in their bodies for longer, as the fat acts as a kind of reservoir. This means that THC can be released again after a longer period of time and can be detected in the blood.
Conversely, a lower body fat percentage means that THC is broken down and excreted more quickly.
Method of consumption (e.g. smoking, oral intake)
The method of THC consumption also affects how long it can be detected in the blood. When smoked, THC enters the blood quickly, but is also broken down more quickly.
When taken orally, for example in the form of THC gummies or capsules, it takes longer for the THC to enter the bloodstream. At the same time, however, it remains detectable for longer because it is broken down more slowly.
Good to know: Waiting time after THC consumption before driving
Recommendations the German Society for Traffic Psychology (DGVP)
- Occasional consumers: After 12 hours, THC is usually below the limit. After 24 hours, you are safe.
- Regular consumption: Can significantly extend the detection time of THC. It usually takes 3-5 days until THC is no longer detectable.
- Oral intake (e.g. cannabis biscuits): Significantly extends onset of action and detection time. Wait at least 24 hours.
- Unclear THC content: For unknown products or high doses, wait at least 24 hours.
- Long-term use: Daily or multiple consumption excludes participation in traffic for weeks.
Detection times: How long does THC stay in the blood?
The time it takes to detect THC in the blood varies depending on the person and the factors mentioned above. However, there are general time periods that can serve as a guideline.
General time periods
THC can usually be detected in the blood for between 1 and 2 days. With occasional consumption, THC can usually no longer be detected in the blood after 24 hours. With regular consumption, however, THC can remain detectable in the blood for up to 7 days. In extreme cases, especially with very heavy consumption, it can even be detectable for up to 30 days.
There are Studieswhich show that there can also be very individual courses. There are cases in which the values do not decrease evenly, but even increase again briefly after several days.
Another Study concluded that the THC levels in the subjects decreased only gradually; only 1 out of 11 participants was completely negative after 26 days.
Example: THC levels in blood as a table
| Period after consumption | THC level in blood (ng/ml) |
|---|---|
Note: These values are guidelines and may vary depending on individual metabolism, frequency of consumption and dosage.
Differences between occasional and regular users
As previously mentioned, occasional users who consume THC rarely or in small amounts have the advantage that the THC disappears from their bloodstream relatively quickly.
Regular users, however, who consume THC more frequently or in higher doses, must expect significantly longer detection times. This is because THC accumulates in the body with repeated consumption and is broken down more slowly.
Comparison to other test methods (e.g. urine, saliva)
While THC can be detected in blood for a relatively short time, the detection times in other body fluids vary. In urine, the most commonly used test medium, THC can be detected for much longer – often up to 30 days in regular users.
In saliva samples, however, THC can be detected in a similar way to blood, namely for about 1 to 3 days. Hair analysis, a less common method, can even detect THC for up to 90 days, although this method can primarily detect long-term consumption.
Lawyer Dr. Michael Hoog says anwalt.de: “THC or the breakdown product THC-COOH can then be detected with a rapid test in saliva, sweat or urine. A urine sample is often taken during police checks.”
Be careful with mixed consumption
“If you take cannabis, if you take opiates, then the risk of an accident is doubled. If you take cocaine, then the risk of an accident increases fivefold, and it is especially dangerous if you use both drugs, because then the risk is increased by five to 30 times.”
Dipl.-Ing. Klaus RobatschHead of Road Safety Research at the Austrian Road Safety Board (Austria)
Conclusion
THC remains detectable in the blood for different lengths of time depending on individual factors. Factors such as dosage, frequency of consumption, metabolism, body fat percentage and method of consumption significantly influence the length of time it can be detected.
Occasional users can often be “clean” within 1 to 2 days of consumption, while regular users can expect much longer detection times, which can last up to 30 days. There is no reliable method to speed up the clearance of THC, as this depends heavily on personal health factors.
FAQ
Will THC still be detectable on a drug test after one night?
Yes, if you consumed THC the night before, it may still be detectable in a blood test the next day. Generally, THC can be detected in the blood for 1 to 2 days, depending on the dose and frequency of consumption. Especially with occasional consumption, the probability of the test being positive is high.
How long does it take for THC to completely disappear from the body?
The time it takes for THC to completely disappear from the body depends on various factors, such as frequency of consumption, body fat percentage and metabolism. THC can usually be detected in the blood for up to 7 days after the last consumption, and even up to 30 days with heavy and regular consumption. However, THC can remain detectable in urine for much longer, sometimes up to a month or more.
What can you do to remove THC from your system faster?
There is no guaranteed method to remove THC from the body faster. However, a healthy lifestyle with plenty of exercise and adequate hydration can boost metabolism and potentially speed up the breakdown of THC. However, there is no surefire method to significantly shorten the detectability of THC, as the breakdown is highly dependent on individual factors.
