Drug addiction: the effects of cocaine and more

Cocaine, MDMA or cannabis: drugs are widespread despite their illegality. But drugs can have devastating effects on the mind and body. Find out the most important facts about the effects and properties of different drugs.

23.03.2023 Nina Merli

Addiction often creeps up on victims. Whether alcohol, nicotine or drugs: the lines between occasional consumption and addiction are often blurred. People quickly get used to an intoxicant and often don’t stop using drugs despite the side effects. The illegal substance becomes more and more all-consuming and defines the day-to-day life of users. The WHO (World Health Organisation) defines addiction as “a state of periodic or chronic intoxication produced by the repeated consumption of a drug (natural or synthetic)”.

According to the Federal Office of Public Health (FOPH), more than 200,000 people of working age in Switzerland smoke cannabis at least once a month. Twice as many reported having tried another illegal substance at least once in their life. Cocaine is the most sold drug in Switzerland after cannabis.

The effect of drugs on body and mind

Drugs are psychoactive substances. This means that they influence our perception, our thoughts and our feelings. Taking drugs activates more than 86 billion of the brain’s nerve cells, boosts the release of dopamine and elicits a strong learning signal. With regular consumption, the brain develops an expectation that is never satisfied – leading to drug addiction.

How do drugs affect the body? Depending on the substance, the effects can be stimulating, dulling or hallucinogenic. Users may feel very relaxed or sleepy, but also excited, euphoric and full of energy. Feelings of happiness, megalomania, fear and paranoia – drugs can have completely different effects depending on the substance, quantity, personality and genetics.

Side effects and consequences of drug use

Not all drugs cause the same reaction. But all drugs can leave serious physical and psychological damage. The physical reactions can sometimes be very severe. For example, some drugs, such as cocaine, ecstasy and heroin, can lead to strokes, heart attacks or, in the worst case, death – even when used just once. The extenders added to the drugs can also have significant side effects and lead to long-term consequences – like levamisole, for example, in the case of cocaine.

Drug addiction also leaves its mark on the mind: chronic drug use can change personalities and make addicts aggressive, anxious or depressed. Certain drugs can cause psychosis. 

Drug addiction usually has social consequences as well: financial worries, neglect of interests or isolation from friends and family are just some of the problems that an addiction brings with it. It is not only drug addicts that suffer from this, but also the people close to them. Addiction is incredibly stressful for the relatives of those affected. What can you do to help? And where can you yourself get help as a family member?

We answer these questions in our article “How relatives can recognise signs of addiction”.

Which drugs are most addictive?

The serious consequences of hard drugs like heroin and cocaine are known to many. But milder drugs can also have a negative impact on health and quickly lead to addiction. A few years ago, the famous medical journal The Lancet published a ranking of the most addictive drugs:

  1. Heroin
  2. Cocaine
  3. Nicotine
  4. Barbiturates (predecessor to sleeping pills)
  5. Alcohol

Wege aus der Sucht

Find out the most important facts about this in our article “Escaping addiction”.

You can get professional support here, among other places:

The effects of cocaine

Taking cocaine has a physically and mentally activating and stimulating effect.

The physical effects of cocaine:

  • Motor hyperactivity
  • Increase in body temperature, blood sugar level, heart rate and blood pressure
  • Reduced hunger and thirst
  • Increased wakefulness

Behaviour after taking cocaine

In many cases, coke, as cocaine is also known, can cause a change in personality. As cocaine blocks the reuptake of certain neurotransmitters such as noradrenaline, serotonin and dopamine, the drug has a strong effect on the behaviour and personality of users. Immediately after taking it, users feel euphoric, and usually more sociable, energetic and uninhibited. Users develop fantasies of omnipotence and judgement is impaired.

How do you recognise a cocaine addiction?

Cocaine is considered the drug with the highest psychological dependence potential. Even using it once can lead to a strong urge for coke. Thoughts constantly revolve around the next “line”. Addicts cannot relax until they have sourced their next high. The following symptoms also suggest a cocaine addiction:

  • Cravings: the desire to take cocaine gets stronger and stronger
  • Developing a tolerance: it takes more and more cocaine to achieve the desired effect
  • Neglecting hobbies and friendships
  • Continued use despite consequential damage
  • Reduced ability to control consumption: users seems to lose grasp of place, time or quantity

Cocaine withdrawal symptoms

Cocaine withdrawal is primarily psychological in nature. It may also trigger physical complaints such as sleeping problems or severe exhaustion, but the typical withdrawal symptoms include:

  • Depression and suicidal tendencies
  • Restlessness
  • Confusion
  • Irritability
  • Violence and aggression

Cocaine: side effects, consequences and damage

Using cocaine regularly for an extended period of time can have severe consequences for the body:

  • Impaired consciousness through to coma
  • Seizures
  • Chronic bronchitis
  • Hallucinations
  • Palpitations, high blood pressure
  • Paralysis of the respiratory system
  • Heart attacks, strokes
  • Liver damage
  • Damage to the nasal mucous membranes and nasal septum (from snorting cocaine)
  • Increased body temperature

Added extenders can also have serious side effects and long-term consequences; like levamisole, for example, in the case of cocaine.

The effects of MDMA/ecstasy

MDMA is a fully synthetic amphetamine derivative, known as ecstasy since the 1980s and used primarily as a party drug. Ecstasy has a euphoric and stimulating effect as the MDMA contained in it triggers a higher secretion of the body’s own messenger substance, serotonin, also referred to as the happiness hormone.

Physical effects of MDMA:

  • Accelerated pulse
  • Enlarged pupils
  • Increase in body temperature and blood pressure
  • Sweating
  • Altered visual perception
  • Teeth grinding
  • Dry mouth
  • Dizziness and nausea

Behaviour after taking MDMA/ecstasy

MDMA is mainly taken at parties. The neurotransmitters serotonin, noradrenaline and dopamine are involved in the effect. Users feel relaxed, obliging, euphoric. The need for physical contact is increased. Feelings of hunger and thirst are reduced, fatigue disappears – nothing stands in the way of hours of dancing. With MDMA, however, the effect is not the same for all users, even if they take the same thing. It is heavily dependent on the mood before taking it and also on the setting and the people with whom you take it.

How do you recognise an MDMA/ecstasy addiction?

Unlike heroin or cocaine, MDMA almost never leads to physical dependency – and very rarely to psychological dependency. Taking ecstasy regularly can, however, lead to the development of a tolerance. This means that users increase the dose to achieve the desired effect.

MDMA withdrawal and withdrawal symptoms

As serotonin levels are depleted when MDMA is consumed, it usually takes about a week for these to be replenished. Frequent ecstasy use reduces the positive effect as levels no longer fully replenish. This results in depressive moods, fear and listlessness.

Side effects, consequences and damage of MDMA/ecstasy

MDMA primarily damages the synapses. Excessive and regular use of ecstasy leads to changes in brain function: severe memory and anxiety disorders can occur. Acute side effects associated with MDMA use include the following complications:

Overheating due to additional movement (dancing) can lead to:

  • Circulatory collapse
  • Liver and kidney failure
  • Muscle cramps
  • Confusion
  • Coma

The effects of speed

Because of its appetite-suppressing effect, speed is also used for slimming. As speed increases concentration and performance while suppressing fatigue and the need for sleep at the same time, the drug is often used – like cocaine – to increase performance in the world of work.

Physical effects of speed:

  • Increased blood pressure
  • Reduced hunger and thirst
  • Increased pulse
  • Rapid breathing
  • Increased body temperature
  • Cramps
  • Restlessness, shaking
  • Headaches

Behaviour after taking speed

Originally developed as an appetite suppressant, speed is now mainly consumed on the party scene. Speed has a strong stimulating effect and also increases self-confidence. Speed leads to a distinct urge to speak and move.

How do you recognise a speed addiction?

Speed has a high dependency potential. Thoughts constantly revolve around the drug (cravings), you can no longer imagine a party without speed and gaps between using get shorter and shorter. Bad skin, so-called “speed pimples”, can also be an indication of a speed addiction. As with other drug addictions, aggressiveness, nervousness, sleep disturbances, paranoid thoughts, hallucinations or depressive moods can be indicators of speed addiction.

Speed withdrawal and withdrawal symptoms

Withdrawal from speed usually takes one to two weeks. This usually leads primarily to psychological complaints such as fatigue, restless sleep, irritable mood, outbursts of violence, anxiety, panic attacks, depression and suicidal thoughts. Physical withdrawal symptoms of speed mainly include sweating, shaking, visual disturbances, weakness and severe fatigue.

Speed: side effects, consequences and damage

The side effects of speed become apparent relatively quickly when consumed regularly:

  • The immune system is weakened, leaving users more susceptible to infections
  • The risk of a heart attack increases
  • Greater risk of stroke
  • Calcium deficiencies can lead to teeth and bone issues
  • Itching with micro-hallucinations of insects under the skin
  • Organ damage
  • Pulmonary oedema

The effects of cannabis

Marijuana, hashish, hash, weed: cannabis is the most commonly used illegal drug in Switzerland. One-third of the Swiss population over the age of 15 has smoked a joint at least once in their lives. The cannabis plant contains about 400 ingredients: the best known are THC (delta-9-tetrahydrocannabinol) and CBD (cannabidiol). THC has a hallucinogenic effect and creates a feeling of intoxication, while CBD has a calming effect and can also dampen pain.

Physical effects of cannabis:

  • Serenity, relaxation
  • Altered perception of time and concentration difficulties (from THC)
  • Dry mouth and dry throat
  • Reddened conjunctiva
  • Blood pressure changes, muscle relaxation
  • Lower skin temperature (cold feeling)
  • Antipsychotic, antidepressant and analgesic (from CBD)
  • Panic, anxiety, paranoia, paranoid delusions
  • Increased heart rate

Behaviour after taking cannabis

Cannabis has the property of reinforcing the current mood of the user: as such, it reinforces negative as well as positive feelings. Smoking weed can trigger an urge to talk and laugh, longer reaction times or concentration disorders.

How do you recognise a cannabis addiction?

The dependency potential of cannabis is much greater than publicly assumed. Cannabis can be addictive. As a regular cannabis user, you can no longer imagine handling certain situations without a joint.

Cannabis withdrawal and withdrawal symptoms

Cannabis withdrawal: typical symptoms are cardiac arrhythmias, insomnia, sweating, diarrhoea, stomach problems, nausea and vomiting. On a psychological level, there is nervousness, inner restlessness, aggression and depression. These withdrawal symptoms usually begin 24 to 48 hours after the last use. Duration of withdrawal: about 1 to 2 weeks, which happens in stages.

Cannabis: side effects, consequences and damage

Long-term cannabis use can have a negative impact on concentration, alertness and lung function. Cannabis can have a harmful effect on brain development – especially in adolescents. People who have a vulnerability (genetic susceptibility) to schizophrenia may develop schizophrenia through the consumption of highly potent cannabis strains and synthetic cannabinoids.

Typical physical cannabis side effects are an increased risk of respiratory inflammation, shortness of breath, chronic coughs and bronchitis. Because cannabis is usually smoked with tobacco, there is also a greater risk of cancer.

The effects of LSD

The former hippie drug has increasingly developed into a fashion drug in recent years – it is taken at parties mainly as a “micro-spray”, i.e. as a spray with low dosage. LSD produces profound changes in consciousness: perception of time and space is altered, sensory illusions (hallucinations) occur.

Physical effects of LSD:

  • Fluctuating body temperature
  • Accelerated heartbeat
  • Numbness
  • Cramps
  • Respiratory problems
  • Nausea
  • Enlarged pupils

Behaviour after taking LSD

Users may have visual and auditory hallucinations – these can vary greatly depending on the person. Microdosing primarily boosts mood and you feel “tipsy” – but the typical LSD effect can also occur during microdosing, depending on the amount you take. How long does the effect of LSD last? Between 8 and 12 hours – depending on the amount taken. LSD use can trigger horror trips with panic attacks, paranoia, crying fits and fear of death.

How do you recognise an LSD addiction?

LSD is not known to cause physical dependency. Psychological dependency is another story: particularly after a “good trip”, the user wants to experience the feeling again.

LSD withdrawal and withdrawal symptoms

In the case of LSD, there are no typical signs of physical dependency or withdrawal symptoms.

LSD: side effects, consequences and damage

Although LSD does not create dependency, taking it is still risky because LSD use can trigger psychosis. It can also lead to flashbacks: several weeks after taking LSD, you experience a state of intoxication again – without drug use.

The effects of heroin

Heroin acts like morphine, only stronger, and it gets to the brain faster. Heroin has a calming, analgesic, euphoric effect. Self-confidence increases, anxiety and tension decrease.

Physical effects:

  • Narrowing of pupils
  • Low body temperature 
  • Fatigue

Behaviour after taking heroin

Heroin is generally smoked (foil smoking) these days, sometimes snorted and also still injected. If someone has taken heroin, they usually appear relaxed and calm. Unlike drugs like cocaine or speed, someone on heroin is more introverted.

How do you recognise a heroin addiction?

Heroin is the most addictive drug, both physically and psychologically. Addiction starts after one or two weeks of regular use. The body develops a tolerance, which means that addicts need more and more heroin to avert withdrawal symptoms.

Heroin withdrawal and withdrawal symptoms

If you stop taking the drug, the first symptoms of withdrawal appear after about 8 hours. Heroin withdrawal is physically very violent. Symptoms range from sweating, freezing, trembling, very severe body aches, diarrhoea, vomiting, pain and sleep disorders to circulatory collapse. Anxiety and panic attacks also occur. Acute heroin withdrawal usually lasts three to six days. 

Heroin: side effects, consequences and damage

Heroin is very harmful to the body. Contaminated heroin can cause liver damage or gastrointestinal disorders, and smoking heroin can cause respiratory damage. Dirty, shared syringes can also transmit HIV, hepatitis or other pathogens.

The effects of crystal meth

Crystal meth (methamphetamine) is a fully synthetic stimulant that is closely related to speed. As such, the effect of crystal meth is similar to that experienced taking speed, but much stronger and more persistent: while the speed effect lasts six to eight hours, the effect of crystal meth can last anywhere from 16 to 48 hours.

Physical effects of crystal meth:

  • Severe physical agitation
  • No hunger or need for sleep
  • Increased pulse rate and blood pressure
  • Accelerated breathing
  • Enlarged pupils, wide eyes
  • Impaired vision
  • Headaches
  • Dry mouth
  • Disruption to thought and concentration

Behaviour after taking crystal meth

Crystal meth boosts sex drive and the need to talk. The drug leads to an extreme increase in self-esteem (megalomania). Crystal meth users lose awareness of injustice and inhibitions. They can attract attention through intrusive behaviour.

How do you recognise a crystal meth addiction?

The addictive potential of crystal meth is enormous. Crystal meth triggers feelings of happiness, well-being, confidence and hyperactivity. On crystal meth, you feel like you can handle anything. That's why crystal meth addicts feel a strong desire to take more and more of the drug more and more frequently.

Crystal meth withdrawal and withdrawal symptoms

Withdrawal symptoms can occur even after only using crystal meth once: headaches, body and joint pain, feelings of anxiety, sleep disorders and night sweats, irritability, nausea and vomiting are the consequences. If you use crystal meth regularly and decide to go into withdrawal, you will have to deal with the same symptoms – only these will be more intense and last longer.

Crystal meth: side effects, consequences and damage

As feelings of hunger, thirst, pain or fatigue are not perceived during crystal meth use, it can lead to very dangerous side effects such as tachycardia up to a complete mental and physical breakdown. Severe weight loss, damage to teeth, cerebral haemorrhage, kidney damage and an increased risk of stroke are other consequences of a crystal meth addiction.

Drug addiction – not a life-long fate

Whether ecstasy, cocaine or speed – drug addiction has nothing to do with a lack of discipline or personal weakness. It’s a serious but treatable illness. Getting help is the first step towards recovery.

Read more

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