How Continued Drug Use Leads to an Overdose

How Continued Drug Use Leads to an OverdoseDrugs and alcohol contain various chemicals that can damage both the body and mind. Some drugs can be dangerous the first time they are used while others are more dangerous with continued use. As a result, an overdose on drugs can be accidental or intentional, but both can be fatal. Most overdoses occur from either a mix of substances or a very high dose of one substance, but you can avoid this problem if you seek professional help.

Mixing substances is the main cause behind accidental and intentional overdoses. Drug users may be able to handle a typical dose of one substance, but, when they mix that drug with others, the effects that they have together can be both dangerous and fatal. For instance, people often mix central nervous system depressants to create more powerful highs than the depressant can cause alone. People often combine alcohol and heroin, and both substances suppress breathing and overall respiratory function; in other words, this combination can stop breathing altogether if people take too much of them at once.

When people begin abusing drugs, they often try a single substance in small quantities, but continuing to abuse drugs often causes people to experiment with higher doses and with many substances at once. In fact, the longer people abuse drugs, the more likely they are to take harder and more dangerous drugs. They may take the same dose they usually take, but this time with a new, more potent drug that their bodies cannot handle. As a result, they may experience overdose.

The University of Utah explains what alcohol and heroin can do when people abuse this combination long-term. A large dose of heroin can increase the inhibitory effect of GABA, a neurotransmitter that slows breathing to the point of stopping. Furthermore, alcohol decreases the excitatory effect of glutamate, which eventually slows or stops breathing and leads to unconsciousness1.

Another major factor that leads to overdose is tolerance to drugs and alcohol. With regular use of drugs, the body and mind can become tolerant to their effects, which means that people must take higher doses of the drugs if they want to achieve the same effects as before. However, tolerance will decrease if they cannot go with regular doses of drugs that they are accustomed to. As a result, if someone with a high tolerance to a substance and misses a few days or a week of drug abuse, then the amount he took a week ago may be too high. The dose may be the same that it has always been, but, because there was a lapse in doses, tolerance may have dropped to make overdose more likely.

Some chronic drug users are forced to detox while they are in jail or rehab, so they are at high risk for fatal overdoses if they relapse. Ergo, because tolerance can so greatly influence overdose, it is essential to find help for substance abuse before tolerance builds or drops. Continued drug abuse will inevitably lead to tolerance that will eventually lead to overdose.

It is important for people to know the warning signs of overdose so they can call for help when they need it most. It is imperative that you call emergency services during life-and-death situations, which you may recognize through any of the following signs:

  • Seizure
  • Severe headache
  • Chest pain
  • Breathing difficulties
  • Paranoia, agitation or confusion

When drugs are involved in these symptoms, these scenarios can mean an overdose is either occurring or in the works. People who abuse drugs often hesitate to call the authorities for fear of being caught with illegal substances, but the police are typically uninvolved with calls for an ambulance unless the EMTs deem their presence necessary.

Drug overdoses are serious situations that can be not only life threatening, but also incredibly dangerous if the patient survives. For instance, overdoses can cause irreversible brain damage: drugs can cause the brain to suffer from a prolonged lack of oxygen that leads to coma, seizures and even brain death. If people overdose on drugs, then they can incur any of the following problems due to brain injury:

  • Movement, balance and coordination
  • Hearing and vision
  • Spoken and written communication
  • Thinking, concentration and memory

Some overdoses can cause such high amounts of brain damage that the person can be left in a vegetative state of life2. In short, drug abuse and overdose cause serious problems, so seek professional help as soon as possible to end these problems.

Seek out professional rehab services to stop abusing drugs and to avoid overdose. People can and do recover from drug abuse and addiction every day, but they usually require the help of professional rehab services. Rehab teaches people to overcome their current struggles with drugs to resist relapse triggers in the future. With help, you can get and stay clean from drugs.

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1 “How Drugs Can Kill,” University of Utah,, (Cited January 17, 2016).

2 International Overdose Awareness Day, “Overdose Basics,”,, (Cited January 17, 2016).