I feel as though Psychoactive Substances & Addiction are subjects that many people become interested in gaining knowledge about simply because of how fascinating both subjects are to research.

Even just at the very surface Psychoactive Substances are intriguing because they change how the Central Nervous System functions which can develope into altered states of mood, behavior, cognition, consciousness, or perception. Just the idea that you can ingest a pill, powder, liquid, or crystaline substance and achieve many if not all of those altered states and understanding how they do is quite alluring.

Before diving head first into understanding drug pharmacology and the different mechanisms of action of different drugs. It's best to know what the different Classes or Families of Psychoactive Substances are. Personally I like to use the term Family/Families instead of Classes because I feel the latter has a broader feel. Familiarizing ones self on the different names given to each Family and knowing the essential effects each family produces is the best way to get started. Understanding each Families basic effects allows a person to understand how & why specific drugs belong to those Families. The precise number of how many Families of Psychoactive substances exists varies from article to article and person to person. It is my opinion that there are only 3 PRIMARY Families of Psychoactive Substances. But there are numerous Sub-Families that fall under under the main 3 families. In fact many Psychoactive Substances can belong to more than one of the 3 primary families and can definitely belong to many sub-families. Here is my list of the 3 Primary Familes of Psychoactive Substaces also with the basic details about their positive & negative effects. Typically the positive & negative effects are a direct result of their affect on a person's CNS. Though the positive effects typically present themselves cognitively/psychologically whereas the negative side effects mainly manifest themselves thru the Cardiovascular System but some are also cognitive in nature. Keep in mind that not all Psychoactive Substances that belong to each Family will have all of these positive/negative effects. Instead I'm just detailing said effects broadly and not listing them all.

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•Depressants- calm the brain, reduce anxiety, relax muscles, can produce euphoria or dysphoria and can induce tiredness and/or sleepiness. Negative effects include slow/shallow breathing aka respiratory depression, slowed and even weak pulse, lower blood pressure, depression, self-loathing, & anhedonia. Severe negative side effects are coma, respiratory arrest, & death.

•Stimulants- stimulate the brain and increase alertness, wakefulness, energy, excitability, improve in mood, enhance cognition, most typically produce a false sense of well-being & euphoria. Negative side effects are shortness of breath, tachycardia, heart palpitations, increased blood pressure, sleep deprivation, paranoia, delusions of grandeur, impulsivity, irritability, drastic mood swings & acute psychosis which can lead to suicide ideation and/or attempts. Overdosing or what it's more often called Overstimming can occur but the likelihood of death happening while Overstimming is not a common outcome.

•Hallucinogens- are psychedelic in nature that cause audio/visual hallucinations sometimes seperately but oftentimes in tandem. They also alter one's perception that results in subjective changes in thoughts, emotions, and consciousness. Negative side effects are hypothermia or hyperthermia, increased blood pressure/pulse, rapid breathing, extreme worry, anxiety, paranoia, erratic behavior, acute problems with speaking/thinking, acute memory loss, loosing touch with reality and ones self, acute psychosis(in very rare cases long-lasting or permanent psychosis), suicidal ideation and/or attempts. Overdosing of Hallucinogens more often than not results in a "bad trip", but death is a very unlikely result of overdose. Most Hallucinogenic related deaths do occur during an OD(bad trip) but are usually the result of suicide.
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PLEASE KEEP IN MIND THAT THIS LIST IS MY OPINION AND SHOULDN'T BE INTERPRETED AS SCIENTIFIC FACT!
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