Drugs in the body

Drugs and the body 

This animation shows how drugs travel through your body after you take them. This animation includes sound which can be turned on or off.  

Below we will explain what the different ways of using drugs are and how drugs leave the body:  

Methods of taking drugs 

Drugs are mainly active in the brain where they influence the brain biochemistry. One way or another, all drugs need to reach the brain before they can exercise their effects. There are different ways of taking drugs:  


This includes for example smoking a cigarette or a spliff, smoking base coke, inhaling heroine vapor (‘chasing the dragon’), snorting glue and smoking cannabis through a vaporizer.  

When one inhales, the active compound reaches the lungs. The lungs contain an enormous amount of small blood vessels and through these the drug is quickly taken up into the blood. The blood is pumped around the body by the heart. Inhalation is one of the fastest ways of getting a drug to the brain; within 7 to 10 seconds the drug will reach your brain.  

The user can regulate the intake of the drugs because the user can notice the effect of taking a drug through inhalation quickly. For example, one will stop smoking cannabis when one feels stoned enough.  

Inhalation of drugs damages the lungs.  


For example: injection of heroin, cocaine or speed in a blood vessel, injecting ketamine in muscles.  

Injecting a drug results in a fast and intense effect. When injecting in a blood vessel (intravenous) the effect can be noticed after 15 to 30 seconds and when injecting in the muscles (intramuscular) or under the skin (subcutaneous) after 3 to 5 minutes. 

Upon injection, a large amount of drugs will enter the bloodstream at once and directly. As a result, the injection of drugs will result in a ‘flash’. Other methods of taking drugs can cause euphoria but do not result in a flash (except for smoking base coke/crack).  

Injection is the riskiest method of taking drugs, because one crosses all of the body’s protective barriers. Recreative drug users in the dance scene rarely inject drugs. In the small scene of psychonauts, some people experiment with intramuscular injection of ketamine.  

Intranasal or snorting

For example: Snorting of cocaine, speed, ketamine, etcetera.  

When snorting a drug, one can feel the effect after several minutes. Thus, snorting is also a fast method of taking a drug. The nasal mucosa contains many small blood vessels through which the drugs is taken up into the blood. The heart pumps the blood around and in this way, the blood with the drug will reach your brain (so the drug will not directly go from the nasal mucosa to the brain).  

When one snorts drugs regularly, the nasal mucosa will become irritated or inflamed. In extreme cases, this can lead to a chronic common cold or partial loss of smell and taste.  

Oral/eating or swallowing 

For example: swallowing an XTC pill or a speed bomb, drinking alcohol, eating edibles/space cake.  

Eating or swallowing drugs is a slow method of administration. When the drugs reach your stomach, they will enter an acidic environment, which can partially break down the drugs. In the stomach, but mainly in the small intestine, drugs are taken up into the blood. The blood flowing from the small intestine first goes to the liver. Here, a part of the drugs can be broken down as well. Only after that, the blood will go via the heart to the brain. Because of the long way the drugs need to travel before reaching the brain, it can take about 30 to 90 minutes (depending on the stomach contents) before one notices the effects of the drug. Because a part of the drugs is broken down by the liver before it reaches the brain (which is termed the first pass effect), a higher dose is usually necessary as compared with other administration methods.  

The disadvantage of eating or swallowing drugs is that the intake is more difficult to regulate. One can easily take too much because the drug only starts to work after it has been in the body for a while (for example edibles/space cake).  

Rectal/anal or vaginal

For example: rectal administration of XTC. 

With rectal administration, drugs are taken via the anus. This is not often done by recreational users (it’s not a very nice or comfortable way of using drugs). When taken rectal, the drug is taken up in the blood stream through the rectal mucosa. Because the blood from the rectum doesn’t go to the liver first (in contrast to the blood from the intestine) but directly to the heart, this way of administration is not affected by the first pass effect. As such, the dose for rectal administration is lower than the dose for oral administration. Moreover, effects of the drugs are noticed after 15 to 20 minutes. Individuals who suffer from an irritated stomach or nausea after oral administration could consider rectal administration.  

Through the oral mucosa 

For example: keeping a tab of LSD in your mouth for half an hour.

When administrating LSD, many users will not swallow the tab immediately, but keep it in their mouth for a while. In this way, the active compound can be taken up through the oral mucosa into the bloodstream. The effect of the drug occurs faster than with swallowing.  


How do drugs eventually leave your body? 

The liver plays an important role in breaking down drugs. The products formed during this process are called metabolites. These enter the bloodstream and are excreted via the kidneys and urine. Important to note is that one does not get sober faster by snorting cocaine or speed, by drinking coffee or by vomiting. These things cannot reduce the concentration of drugs in your bloodstream. 

Most drugs (cocaine, speed, XTC, LSD) have disappeared from your body after 2 to 3 days and will no longer be detectable in your blood or urine.  

THC – the active component in cannabis – is an exception. After a single use, traces of cannabis can be detected in your blood for up to five days. With regular use (3 times a week for half a year) it can take up to 3 months (!) until all THC has disappeared from your body. This is the case because THC is a fat soluble compound which is stored in your fat tissue, from which it is slowly released in small quantities (from which you cannot get high!) and then excreted.  

Most drugs are, besides being fat soluble, also water soluble and disappear from your body after 2 to 3 days.  

For further information, see the part on detection for the individual drugs in the Drugs ABC.