Cocaine and the Amphetamines

20.02.2021 |

Episode #8 of the course Introduction to drugs and behavior by Dr. Daniel McGrath

 

In the 1980s, cocaine made a huge comeback. Cocaine became the “glamour drug” of Wall Street and in Hollywood. At the same time, a cheaper yet equally potent version of cocaine also made its way into American cities and neighborhoods. Crack cocaine was cheap to produce and could be smoked, providing an intense high for the user. The result was an epidemic of drug use that lasted the entire decade. Today, amphetamines, and methamphetamine in particular, have primarily replaced cocaine to become the dominant illicit stimulant. In this lecture, we are going to take a closer look at both drugs. Let’s begin with cocaine.

Cocaine comes from a plant called Erythroxylon coca, which is grown chiefly in South America. The process to extract it is both extensive and very environmentally toxic. Cocaine hydrochloride is the form of cocaine that can be snorted and absorbed through nasal membranes or injected intravenously with a syringe. Freebase cocaine is cocaine in its base form, meaning that drug molecules are separated from the salt. Freebase can be heated in a vapor using a pipe and then inhaled. Crack cocaine is the salt mixed with baking soda and heated to make crystals or rocks. These rocks are then heated in a pipe with water, creating a vapor that is inhaled. Smoking cocaine leads to a very fast high that peaks in less than a minute, whereas snorting cocaine can take 15 minutes to reach a high.

When cocaine reaches the brain, it has powerful effects on the neurotransmitters norepinephrine, serotonin, and dopamine. Cocaine blocks the reuptake of these neurotransmitters, meaning that more dopamine is left outside of the pre-synaptic cell to be absorbed by post-synaptic neurons. This ultimately creates intense feelings of energy, euphoria and becomes incredibly reinforcing. The half-life of cocaine is around 45 minutes, meaning the whole experience is relatively short.

Acute effects. Cocaine produces an intense rush soon after it is used. Users report feelings of euphoria, elevated mood, talkativeness, and increased libido. However, other people will display heightened anger and aggression. The elevated mood is often accompanied by a “crash” in the mood once the effects of the drug wear off. Cocaine can also be very dangerous, even after using it just once. For instance, it can quickly elevate blood pressure and constrict blood vessels, increasing the immediate risk of heart attacks or stroke. These physiological effects create a serious risk of overdose and death.

Chronic effects. In addition to acute harms, people who use cocaine over the long-term face a whole host of potential health issues. For example, cocaine destroys cells in the nasal mucosa when snorted over a long period of time, resulting in a deviated septum (a hole between nostrils). Among those who smoke crack cocaine, lung damage can occur as well as other organ damage. The cocaine-induced psychotic disorder can also occur whereby users experience intense hallucinations and delusions.

Amphetamines are a class of stimulant drugs that are synthetically created in underground laboratories. Initially, L-amphetamine (known as Benzedrine) was used to treat nasal congestion but was removed from the market in the 1970s due to abuse. However, other amphetamines (e.g., methylphenidate) are still used to treat medical conditions like attention-deficit/hyperactivity disorder (ADHD). The most problematic amphetamine is easily methamphetamine, also known as crystal meth. There is currently a raging methamphetamine epidemic in North America, with substantial year-over-year increases in meth use since the early 2010s. Most often, methamphetamine is smoked but can be injected, snorted, or swallowed. When smoked, the user achieves an intense high in seconds.

In the brain, amphetamine and methamphetamine look very similar to neurotransmitters. In essence, the drug molecule mimics dopamine and actually enters the pre-synaptic neuron. After drug molecules enter the neuron, they work to increase the amount of dopamine released into the synaptic cleft (this is the space between two neurons). In addition, the drug also inhibits the reuptake of dopamine as well as breaking down dopamine. This process results in excess dopamine that can be absorbed by the post-synaptic neuron.

Acute effects. Amphetamines cause extreme feelings of euphoria. For meth, in particular, binge use is common, whereby people continue to use the drug for several days without sleeping. Some people also experience hallucinations, irritation, and aggression. Like cocaine, methamphetamine use poses a concerning risk for overdose. The drug causes increased heart rate and blood pressure, and as a result, possible heart attacks and stroke. An overdose can happen after a single-use.

Chronic effects. Chronic use can result in a host of health problems. First, many users have sores from picking their skin due to hallucinations of bugs crawling under the skin (called “meth bugs”). They often lose weight and have severe tooth decay. Meth use is also linked to a greater risk of heart attack, stroke, and neurological disorders. Lastly, IV users are also at risk for bloodborne diseases such as HIV if they share needles.

Addiction potential. Intense dopamine transmission makes both cocaine and amphetamines highly addictive compared to other drugs. At present, there are no approved medications to treat either cocaine or methamphetamine addiction. Treatment typically involves supervised detoxification followed by behavioral interventions like cognitive behavioral therapy or other psychotherapies.

That’s it for today; tomorrow, we are going to move on to opioids. See you then!

 

Recommended book

Cocaine and Methamphetamine Addiction: Treatment, Recovery, and Relapse Prevention by Arnold Washton and Joan Ellen Zweben

 

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