Side Effects of Drugs and the Cost to the Body

Most people are aware of the many health problems that can be caused by drug use. Though some individuals can get by with occasional substance use, every intoxicant has side effects and most are addictive in some form or another. Many also carry the risk of potentially deadly overdose, the risk of which can be increased by lack of experience and a low tolerance to the drug.

Which side effects, short-term and long-term, will arise during drug use depends largely on the type of drug. Many substances, including prescription medications, carry a minor risk of severe side effects emerging during their first use. These can include allergic reactions or psychological reactions such as panic attacks, hallucinations, and psychosis (loss of connection to reality). Some people are naturally more sensitive to intoxicants and therefore are more likely to experience rare side effects and/or overdose.

Even if they’re severe, short-term side effects typically lessen after a couple weeks of use or shortly after the drug leaves the system. The bigger risk comes from long-term use of substances. Many drugs, including a good amount of prescription medications, will cause damage to the body over time. Some of these effects can be irreversible and change a person’s life. This is one of the reasons that addiction is such an alarming condition that needs to be treated by medical professionals. Unfortunately, out of the 23.5 million people in the US age 12 or older, only 2.6 million (11.2 percent) received treatment in 2009.

The most common general drug classes are stimulants, depressants, opiates, and hallucinogens. Each type of drug has its own distinct set of common side effects and long-term health effects.

Stimulant Abuse


Stimulants include cocaine, methamphetamine, and prescription drugs like Ritalin and Adderall. These drugs stimulate the central nervous system, creating a burst of energy, increased focus and alertness, and often feelings of invincibility – like there’s nothing you can’t do. If abused, this is typically followed by a crash that produces fatigue, depression, and irritability.

Typical side effects of stimulants can include:

  • Anxiety
  • Restlessness
  • Agitation
  • Increased heart rate
  • High blood pressure
  • Increased body temperature
  • Insomnia
  • Headache
  • Loss of appetite or weight loss
  • Abdominal pain
  • Tremors

Anyone with a history of heart problems or seizures should avoid stimulants as increased blood pressure puts stress on the heart, and seizures tend to be a rare side effect as well. High blood pressure can also increase the risk of stroke. There have been cases of individuals dying from sudden heart failure or stroke after taking a stimulant even if they hadn’t been abusing it before. There have also been cases of reported panic attacks and psychosis.

Unfortunately, there’s a rising trend of young students using prescription stimulants meant to treat ADHD to help them complete their schoolwork. One study found that one in five college students has used a prescription stimulant like Adderall, compared to one in seven people of the same age not enrolled in college. This has led to a rash of addiction disorders and other health problems in these individuals.

Typical side effects of stimulants can include:

Stimulants work by releasing a cocktail of various neurotransmitters in the brain associated with pleasure and energy. While it might feel great in the moment, after a period of regular stimulant use, the brain starts to compensate by releasing lesser amounts of these neurotransmitters on its own. This is how a tolerance develops, and it’s why addicted individuals experience withdrawal symptoms that can include serious depression and fatigue after intake of the drug stops. The brain is no longer releasing the neurotransmitters necessary to give them a normal amount of energy and happiness.

For the most part, the brain will readjust back to its prior state after several days of abstinence from the stimulant. However, the brain is an incredibly complex organ, and after enough drug abuse, the changes that result may not be entirely reversible. Long-term users have reported continuing cognitive problems and emotional disturbances long after quitting.

The physical effects of stimulants can be just as damaging. The constant increase in heart rate and high blood pressure can wear on a healthy heart over time. Blood vessels and heart muscles can weaken, increasing the chance of heart disease, irregular heartbeat, and heart attack. High blood pressure is also hard on the kidneys and increase the chances of dementia, stroke, and aneurysm. At the same time, there appears to be link between stimulant abuse and the later development of Parkinson’s disease.


depressing the central nervous system
Depressants are, as the name suggests, basically the opposite of stimulants. Drugs in this class tend to come in pill form and are available via prescription, including benzodiazepines (Xanax and Klonopin), barbiturates (Amytal and Seconal), and antipsychotics (Zyprexa and Haldol). These medications are used to fight anxiety, panic disorder, and certain muscle conditions like restless leg syndrome or even seizure disorders, as well as disorders that include psychotic symptoms. Alcohol is also considered to be a depressant and carries a large range of potential long-term health effects.

By depressing the central nervous system, these substances tend to produce feelings of calm and relaxation, and promote sleep. The effectiveness of these drugs also makes them vulnerable to being abused and gives them a serious addiction potential. The abuse of prescription drugs like these has spiked in recent years, leading to an alarming increase in overdose deaths as people get them on the street and at parties without knowing the dangers of these substances. In the US, these deaths topped 25,000 in 2014, more than doubling since 2001. Benzodiazepines themselves saw an fivefold increase in overdose deaths during the same period.

Common short-term side effects of depressants include:

  • Fatigue
  • Dizziness
  • Confusion
  • Poor concentration
  • Slurred speech
  • Lowered blood pressure
  • Disorientation
  • Loss of coordination
  • Fever
  • Depression
  • Difficulty urinating
  • Visual disturbances

Though most of these will fade, psychological issues and fatigue can persist as the brain is constantly put into a depressed state. At the same time, though these drugs tend to make people sleepy, the sleep people get on them is not of a good, normal quality. They can actually make people more and more tired over time, and sleep deprivation has recently been found to potentially lead to irreversible brain damage. Long-term users may experience chronic fatigue, depressive disorders, breathing difficulties, and sexual dysfunction long after ending their use.

Common side effects of depressants
Benzodiazepines in particular can cause serious long-term issues after a person stops taking them. A phenomenon referred to as rebound anxiety has been observed in many patients who were put on one of these medications for an anxiety disorder. In these cases, patients experience significantly worse anxiety after they stop taking their medication than they did before they started taking it. This anxiety can take a year or more to overcome and often requires other medications and therapy to do so.

Alcohol by itself affects a large number of different parts of the body, including the brain, heart, liver, kidneys, pancreas, lungs, and gastrointestinal system. It’s also associated with a number of cancers, including cancers of the stomach, colon, and liver. Alcoholic liver disease is a serious problem among those addicted to alcohol, and those who use alcohol heavily for many years may experience a number of cognitive problems, including difficulty with basic motor functions like walking.


effects of opioids on body
Opioids refer to all drugs that interact with the opiate receptors in the brain. Many of these were derived directly from the opium plant, such as morphine and heroin, and there are also synthetic and semisynthetic opioids like hydrocodone, which is found in the popular painkiller drug Vicodin, and oxycodone, found in OxyContin.

These drugs also depress the central nervous system, but their main function is to block pain. Many of these drugs, including morphine, are considered essential to any nation’s healthcare system as they’re needed to manage pain, sedate patients, and prevent injured people from going into shock and dying. Medications like Vicodin and OxyContin are prescribed to treat moderate to severe pain in people who have recently had surgery or who have painful conditions like back problems. The success of these drugs led to a rising number of prescriptions dispensed, peaking in 2011 at 219 million.

Opioids are, of course, notorious for being addictive. Abusing one of these drugs can produce an intense, euphoric high that tempts many people to try them. Heroin is one of the most powerful opioids in existence. Because it’s so dangerous and has no medical application, it’s been classified as a Schedule I substance in the US. Despite efforts
to combat abuse and addiction, heroin continues to harm communities at epidemic proportions.

In addition to euphoria and pain relief, most opioids have many short-term side effects, including:

  • Nausea
  • Vomiting
  • Dizziness
  • Constipation
  • Sedation
  • Slowed breathing

One of the most dangerous things about opioids is their tendency to seriously depress the respiratory system. Especially if combined with other depressants, breathing can slow to the point that not enough oxygen is getting to the brain – a condition called hypoxia. This can quickly lead to coma, irreversible brain damage, and death.

Even if brain damage from overdose is avoided, research has found that long-term abuse of opioids seems to cause a reduction in white matter in the brain. The white matter is largely responsible for carrying signals between other parts of the brain (the gray matter). A loss of this can effect decision-making abilities, stress management, and behavior regulation.

Long-term opioid abuse also causes chronic constipation, which can lead to a number of health issues and even damage to the colon. This is because opioids slow the entire gastrointestinal system down. Constant respiratory depression also causes an increased risk of lung infections. Plus, the tendency for opioids like heroin to be injected exposes users to further infections that can weaken the heart, plus the risk of contracting dangerous diseases like HIV and hepatitis C.


The side effects of hallucinogens
The side effects of hallucinogens are more variable between individual drugs due to their unpredictable nature. Not all of these drugs are considered to be physically addictive, and they tend not to be abused as often as other classes of drug. However, they can have some serious short-term and long-term health effects, especially on the psychological side.

Hallucinogens are meant to cause visual, auditory, and tactile hallucinations, and changes in perception of reality, as well as changes in thought and consciousness. These can include LSD, MDMA (ecstasy), cannabis, mescaline, DMT, ketamine, PCP, and salvia. According to the National Survey on Drug Use and Health, 15 percent of Americans age 12 and older have used one of these drugs at least once in their lifetime. Common side effects of psychedelics include:

  • Increased heart rate
  • Increased blood pressure
  • Heightened body temperature
  • Nausea and vomiting
  • Loss of appetite
  • Muscle rigidity
  • Inability to move muscles
  • Anxiety
  • Panic
  • Paranoia
  • Delusions
  • Mood swings
  • Loss of a sense of identity

The most immediate danger of these drugs is what is called a “bad trip.” This happens when hallucinations and perceptual changes become frightening or enraging, or when the user loses touch with reality (psychosis). In these cases, people can occasionally become violent in order to protect themselves or in anger. They can injure themselves or others in this state. However, these cases are rare.

There have also been cases in which users of psychedelics or those close to them have reported drastic changes in personality. This is not well understood, nor is this always considered to be a bad thing. Much worse are reports of some individuals having flashbacks to bad trips many years after their use of hallucinogens has ended. With certain hallucinogens like PCP and MDMA, long-term use can lead to severe depression, or withdrawal symptoms can trigger this symptom. In some cases, this can lead to suicidal ideation.