Pathogens (germs) can be transmitted very easily when injecting heroin or other drugs. This includes HIV and hepatitis viruses, which lead to serious liver inflammation. Injecting drugs can also cause abscesses and vein inflammation.
You can protect yourself from infections when using drugs by only ever using your own syringe and equipment. It's generally less risky to snort or smoke drugs than it is to inject them.
But snorting (inhaling) also carries a risk of infection. Therefore you should never share a snorting tube with other people.
In general, you should try to ensure the most hygienic possible conditions for drug use. This will reduce the risk of infection with viruses, bacteria and fungi.
Using only your own needle and consuming drugs in the most hygienic conditions possible is called "safer use".
Traces of blood on and in the needle and in the syringe can contain a high concentration of HIV and other viruses and bacteria - even if the blood cannot be seen with the naked eye.
You should therefore always use your own syringe. Ideally, you should use a new syringe for every fix.
Many cities have places where you can get sterile syringes for free or for a very low price, or where you can exchange old needles for new ones. Syringe vending machines ("Spritzenautomaten") offer 24-hour access to sterile equipment.
If you are ever in a situation where you cannot avoid using a syringe that someone else has used, it should at least be boiled or disinfected.
If that is also not possible, it is recommended that you snort the drug rather than inject it. This will keep the withdrawal symptoms at bay until you can get a clean syringe.
Pathogens are not only transmitted via syringes, but can also be transmitted via the other equipment used to shoot up drugs. This includes filters, spoons and lighters. Sharing equipment carries, in particular, a very high risk of hepatitis infection. HIV can also be transmitted via shared equipment.
Warning: the water used to shoot up can also transmit pathogens, as it is an ideal breeding ground for fungi and bacteria.
Some drug users share "gear" by first cooking it up, drawing it up into a syringe and then sharing it out according to the measuring lines on the syringe.
Each user uses their own syringe to take their share out of the first syringe. Nevertheless, this method is risky. If the first syringe or needle, the water or the filter has already been used, viruses, bacteria and fungi could be passed on.
There is only one hygienic way to share out drugs: to divide up the powder first. Then each person can use their own syringe and equipment.
Some drugs, especially cocaine and speed, are snorted (inhaled) into the nose using a small tube. Heroin can also be snorted.
The risks associated with snorting are lower than with injecting.
But be warned: tiny cuts or injuries in the mucous membrane of the nose, which can easily be caused by snorting, can allow hepatitis viruses and HIV to be transferred to the tube and then passed on to others. Because the drugs can irritate and injure the mucous membrane inside the nose, viruses can then be especially easily absorbed.
You should therefore always use your own tube!
You should never use rolled-up bank notes for snorting. They have usually passed through many people's hands and can be covered in pathogens.