The overdose is when the level of intoxication reaches the point where you have mental or physical harms. It depends on the substance you took, providing different signs and harms.
Stimulants (Ecstasy, amphetamine-like substances, cathinones, cocaine, speed, etc.):



Wheeze or breath shortness

Difficulty to pee

Restlessness, tremor, spasms, chest pain and rapid heartbeat

Increased body temperature and chills


Very strong headache


Agitated and irascible behavior

Paranoia, hallucinations, anxiety and psychotic behavior.

Sedatives (heroin, opioids, G, ketamine):

Low heartbeat and breath pace

Bluish lips and fingertips

Snoring or yawning

Small pupils


Difficulty to wake up

No consciousness

No breath

As long as some of these signs appear, you have to call an ambulance, and meanwhile:

Check yourself and others who used the same substance

Check whether they respond when you call or touch them

Keep free mouth and nose of those who are sick

If they breathe normally put it lying down, with legs and head on the recovery position, preventing to ingest their vomit

If they do not breathe, start cardiac massage, with 30 compressions on the breast every two breaths.