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The Most Addictive Drugs

Brenda Munnerlyn, RN, BSN

Medically reviewed by

Brenda Munnerlyn, RN, BSN

April 8, 2019

In many ways, it isn’t easy to simply name the most addictive drugs, as those who become addicted to them are unique in their predispositions, individual tendencies, and exposures. However, there are drugs that—because of their chemical compounds and the effects each has on the brain—can take hold of a person in a death-grip that supersedes genetic tendency.

Dependence on drugs can begin very quickly after use, in some cases. In other cases, it may take longer, but the dependence could be much greater, meaning that withdrawal from the substance would be more difficult and even dangerous. Some drugs are to potentially dangerous to the user that using them just a few times can have them hooked or be lethal.

The following are considered the most addictive drugs by researchers at the University of Chicago. They are rated thus by both the ease and rapidity of dependence, and the ease of withdrawal and removal of the substance from the individual user’s life.

Top 10 Most Addictive Drugs

Nicotine: Likely the most addictive substance that we abuse is nicotine. This drug is a plant alkaloid that attached to a major neurotransmitter, more important than the opioid receptors that heroin saturates. The neurotransmitter that is affected by nicotine intake is central to nerve functions such as memory. Nicotine also binds to white blood cells, which function as a defense against disease and foreign properties.

Methamphetamine (smoked): Methamphetamine is about three times as powerful as cocaine. In its nature, it is among the quickest of drugs to promote dependency. As a stimulant, methamphetamine causes the brain to release dopamine—ten times the normal release that the brain prompts—which produces pleasurable feelings. Though natural amounts of dopamine simply make us content and at times give us a sense of healthy euphoria, methamphetamine enhances the euphoria in an unnatural, intoxicating high. The drug affects the brain for up to 12 hours and its damage to the brain can take around 2 years to repair.

Crack Cocaine: Smoked crack cocaine enters the bloodstream at such a rapid rate that the high it produces comes on quickly. In fact—as a general rule—when a drug is smoked, it reaches the brain in around 7-10 seconds. Cocaine, in itself, produces extreme cravings. Therefore, crack cocaine, smoked instead of snorted, quickly enters the body, produces an enormous high, and leaves an intense craving that is often considered more psychological than anything. Common dependence brought on by the use of crack cocaine is similar to that of snorted cocaine: the rush it gives the user leaves him in a state of great despair afterward. The intensity of negative emotions makes the user crave the better feelings once again.

Crystal Meth: Many people who use crystal meth—methamphetamine in crystalline form—have said that they became addicted after their first use. The use of crystal meth can encourage intense, violent behavior. Users may have moments of psychosis, delusions, and unexplained irritability. Many cases of domestic violence that seem to have no rational beginning are connected with crystal meth use. Though a user may present themselves as being violent or angry, the way the drug makes them feel is similar to the feeling of cocaine. The high is fast, intense, and makes a state of normalcy feel utterly depressing; crystal meth, therefore, ropes the user in who is evading the downer on the other side of the high.

Valium (Diazepam): Most commonly used for the treating of anxiety, Valium is a legal drug on which many people become very dependent. Those in the medical field state that the drug is more addicting in a psychological and emotional context than that of a physical craving. However, the physical dependence is very present, as those attempting to come off of the medication often go through pain, intense nausea, and panic attacks.

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Diazepam—Valium’s generic name—affects the brain receptor GABA, which released the GABA neurotransmitter, the main function of which is to “calm” the individual when there is a chemical imbalance of any kind that promotes negative and severe emotion. Because the emotional stimulus is so great, tolerance to the drug is quick, causing it to become less effective over time. The more one “feels” they need, the more they take as doses become seemingly useless.

Quaalude (Methaqualone): Quaalude—the brand name for methaqualone—is a sedative, hypnotic drug that was in major use in the 1970s. It was used as a relaxer and was labeled a safe alternative to barbituates. Soon, this drug was deemed illegal, as many users experienced vomiting, blood pressure drops, and seizures.

Quaalude is extremely habit-forming as the body becomes continuously tolerant to it. Those who take the illegal form of the once-legal drug have reported having to increase their dose at an alarming rate just to feel its desired effects. Those who began at 75 mg a day can quickly reach 2000 mg a day depending on how the individual’s body adheres to a course of tolerance.

Seconal (Secobarbital): This drug is prescribed to those who are suffering from insomnia. As a sedative, it slows breathing and can produce a pleasurable feeling that often triggers addiction. The drug also has been known to cause unwanted actions amongst users. Many people who take high doses or abuse the drug have been known to eat, shop, talk, and even drive while asleep and on the med.

Addiction of Seconal sets in when users unable to sleep become dependent on the drug to get any sleep at all; much like the body’s addiction to a laxative, the brain ends up trained to shut off for sleep only after the medication is present in the bloodstream. When a necessary function like sleep is at risk, addiction can develop rather quickly.

Alcohol: Studies have shown that those who drink heavily experience a greater endorphin release than those who drink in fewer amounts. Though alcohol abuse and addiction is often viewed as an obvious issue, it is so common an addiction, there is often an oversight of its severity. Research shows that the receptors affected by alcohol are those associated with opioid release. The location of this release in now known to be in the nucleus accumbens and the orbitofrontal cortex. The orbitofrontal cortex is the region of the brain associated with decision-making, while the nucleus accumbens is the region associated with pleasure, reward, and reinforcement. These good feelings that are released during alcohol consumption, as well as the prompt toward the decision-making region of the brain make for a binge-style drinking experience for many users. This lifestyle becomes quickly addictive both physically and emotionally.

Heroin: Also among the most addictive of all drugs, heroin is a substance that is most commonly injected directly into the bloodstream. It is known to be the most quickly acting of all opiates. It produces a high as it binds to and saturates opioid receptors in the brain. These receptors are those that when saturated, mute pain, release endorphins, and cause increasing dependency.

Heroin is one of the most difficult addictions to overcome as its withdrawal process is known to be excessively painful with an accompaniment of extreme illness that can last for days, depending on the amount of the drug that is attempting to leave the body. Those who enjoy the high continue using more while they find they are tolerant to what they once used. Others lean on heroin when the pain of an injury—for which morphine and other relievers is prescribed—is over-treated by a medical professional.

Find Help For Your Dependency

Regardless of how one got to where he is in his struggle with addiction, it is imperative to remember that for every drug there is a recovery. There is a way to treat dependence and start a healthy life. Drugs that are most highly addictive are those that require more intensive therapies and programs to ensure sobriety in the future. Long-term rehabilitation in an inpatient facility may be most fitting, should you find yourself trapped and needing help. Contact for a helping hand today. We can answer your questions and get you where you need to go on your path to sobriety.

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