Cannabis is usually smoked in the form of cigarettes or using special devices (chilum, narghilè). It is normally supplied in the form of: marijuana (the dried flowers, subtending leaves and stems of the female Cannabis plant), hashish (a concentrated cannabis resin obtained from the compressed detached trichomes and fine material that falls off of cannabis flowers and leaves), and hash oil (a THC (Tetrahydrocannabinol) extract that is distilled from the plant using organic solvents). In recent years, the availability of synthetic cannabinoids (herbal mixtures or blends) has also proliferated.
Several studies have revealed that consuming cannabis in adolescence can cause an individual to be increasingly prone to the development of mental disorders (depression, psychosis and affective disorders). It also compromises executive functions, mental processing speed, and causes psychomotor retardation, with the most frequent physical damage related to cannabis consumption affecting the nervous system, reproductive system, respiratory, cardiovascular and immune systems.


Cocaine is a natural organic substance of plant origin that belongs to the alkaloid group. It is extracted from coca leaves by maceration to obtain a coca paste. The paste is subsequently transformed into a salt (hydrochloride). Cocaine saline crystals are ground to obtain a fine white powder. Cocaine can be consumed in different ways:

  • Inhaling: powdered cocaine is inhaled through the nostrils where it is absorbed by the mucous membranes, passing directly into the blood flow.
  • Smoking (crack, free base): ‘crack’ cocaine is formed by means of a chemical process, which involves the use of ammonia or bicarbonate to transform it into a substance that can be smoked. This manner of consumption allows the substance to penetrate the lungs. The name refers to the crackling sound produced when the mixture is smoked.
  • Injection: powdered cocaine is soluble in water. It is therefore possible to inject it intravenously, with immediate effects.
  • Ingestion: chewing coca leaves causes cocaine absorption through oral mucous membranes and absorption through the gastrointestinal tract.

The consumption of cocaine makes the person affected more vulnerable to the onset of psychiatric disorders: mood alterations, anxiety and psychotic disorders, panic attacks, hallucinations and an increased risk of suicide. The most common organ damage is seen in the cardiovascular, nervous, respiratory and reproductive systems, affecting the oropharynx and causing renal and bowel infarction and liver disease.


Heroin is a drug obtained by a process of chemical synthesis, which alters morphine – an alkaloid extracted from the opium poppy – to obtain an extremely fine granular powder which can be white, brown or reddish.

Heroin can be consumed in different ways:

  • Injection: heroin powder is dissolved in a teaspoon with hot water and lemon juice (which makes it more soluble). The liquid is filtered, to eliminate solid residues, and injected intravenously, or intramuscularly, with an insulin syringe.
  • Inhalation: heroin powder is inhaled through the nostrils, where it is absorbed by the mucous membranes, passing into the blood flow. The strongest effects occur after 10-15 minutes.
  • Smoking: Heroin powder is heated on aluminium foil and the vapours inhaled through a tube, allowing the substance to penetrate directly into the lungs.

Inhalation and smoking are often chosen in order to avoid the risk of infection linked to the use of needles, but also due to the incorrect assumption that it leads to a lower risk of becoming addicted.
The most common health damage related to heroin use affects the respiratory and cardiovascular system and results in exposure to contagious diseases such as HIV/AIDS and Hepatitis B or C (use of the same syringe by several people); irregularities of the menstrual cycle; weight loss due to decreased appetite; changes in the composition and production of saliva resulting in tooth decay, an increase in dental caries and severe gum inflammation.