Drug Therapy

You’ve probably heard of people using nicotine patches to wean themselves off of cigarettes or methadone substitutions for those addicted to heroin. Typically, drug therapy aims to reduce the amount of substance the person uses over time through a process known as detoxing, which is a gradual process.

A variety of drug therapies exist that can help treat addiction, and they do so by altering the biological state of the body and the brain. Even addictions such as gambling can be treated with drug therapies, despite not physically consuming or taking a substance.

Inherently, addictions affect a person both mentally and physically, and drug therapies offer a potential solution to both issues.

Drug therapy for addiction, Flaticon

What are the types of drug therapy?

There are three main types of drug therapy used to treat addiction.

Aversives

Aversive drugs can treat substance abuse, such as alcoholism or drug addiction.

Addicts are then encouraged to give up their addiction to avoid the unpleasant outcome of taking substances such as alcohol or drugs. This concept is based on the theory of classical conditioning. At first, the substance is primarily associated with pleasurable feelings. They often induce a sense of relaxation, and some even instigate a state of euphoria (e.g., cocaine).

Removing this association and instead pairing it with a negative result discourages substance abuse.

Alcoholism, Flaticon

Agonists

Agonists treat addictions by lessening the effects of withdrawal symptoms.

Agonists are particularly popular as they allow addicts to essentially wean themselves off of a substance without suffering the uncomfortable (and often painful) effects of withdrawal. Depending on the severity, withdrawal is sometimes enough for a person to retake the drug, as the symptoms are pretty unpleasant. If a person is addicted to alcohol and without it, they have shaky hands, fevers, nausea and vomiting, it is understandable that they would want to avoid these symptoms. It is simpler to drink again, rather than suffer.

Agonists aid this process of detoxing.

Antagonists

Antagonists work differently than agonists.

This process prevents the reinforcement that occurs, which fuels addiction. When a person takes a substance that gives pleasurable feelings, preventing this will directly affect the desire to retake the substance, as it’s not providing the same, intense effects.

However, antagonists are most valuable when used alongside other therapies, such as counselling.

A packet and bottle of drugs, flaticon.com/freepik

Drug therapy in practice

Different drug therapies exist to help treat specific issues.

Nicotine addiction: nicotine replacement therapy

Nicotine replacement therapy uses gum, inhalers, or patches to deliver nicotine in a less harmful way than traditional cigarettes. This therapy provides the addict with nicotine in a clean, controlled dose.

The brain responds in the same way as if the person had smoked a cigarette. The nicotine binds to the nicotinic acetylcholine receptors (nAChRs) in the mesolimbic pathway (where the brain responds to pleasure). It stimulates the release of dopamine (the pleasure hormone) in the nucleus accumbens (central to motivation and action, frequently associated with sexual, reward and drug behaviour).

Over time, smaller and smaller doses of nicotine are given, e.g., smaller patches. Withdrawal syndromes thus become a lot more manageable as there is no shock withdrawal.

Consider the following studies:

• Maity et al. (2014): In this review, they analysed three agents known to be partial agonists to nicotine receptors: Varenicline, Cytisine, and Dianicline. Nicotine interacts with neuronal nicotinic acetylcholine receptors (nAChRs), which releases neurotransmitters such as dopamine and noradrenaline upon activation.

• The three partial agonists activate the nAChR receptors at lower concentrations than pure agonists, by which we mean nicotine. They help reduce addiction to smoking by maintaining dopamine levels to reduce withdrawal symptoms when a person quits smoking.

• They found that these partial agonists were the most promising drug therapy for reducing and stopping smoking, with one study on Vernicline showing that around 46.4% of people on Varenicline could stop smoking by the end of treatment (Wang et al. 2013). Issues exist with cost, although Cytisine appears to be cheaper than Varenicline.

Gambling addiction: opioid antagonists

Although there are no official drug therapies for gambling addiction, some are being trailed, and opioid antagonists are the front runners. Naltrexone, a drug conventionally used to treat heroin addiction, has been used because of the similarities between gambling and substance addiction recognised in the DSM 5.

A chart showing the DSM characteristics of gambling and drug addictions, Yzabelle Bostyn, StudySmarter Originals

Drug addiction is similar to gambling because the dopamine reward system responds to gambling the same way as it would to drugs such as heroin. Opioid antagonists reduce dopamine release in the nucleus accumbens by increasing the release of another neurotransmitter called GABA. This process effectively reduces cravings associated with gambling.

Evaluating the effectiveness of drug therapy treatments of addiction

Each therapy has its strengths and weaknesses.

Strengths of drug therapy treatments

• Effectiveness of drug therapy, research support: Stead et al. (2012) conducted a meta-analysis of 150 high-quality studies into the efficacy of NRT. They concluded that all forms of NRT are significantly more effective than placebos/no treatment to help smokers quit. The nasal spray was the most effective form of nicotine delivery. NRT users were 70% more likely to abstain from smoking six months after quitting. NRT is also safer than smoking and does not encourage dependence, giving it validity as a treatment for nicotine addiction.

• Removal of stigma: The use of drug treatments to treat addiction removes stigma as it encourages people to view addictions as medical issues. This erodes the view that addictions result from some moral or psychological weakness. Removing this stigma could lead to more research and more people seeking help.

• Convenience: An advantage of drug therapy is its convenience. It is easy to take a pill every day and not work on your thought processes or make behavioural changes.

Weaknesses of drug therapy treatments

• Side effects: Both NRT and opioid antagonists can have severe side effects. The side effects of NRT include dizziness, gastrointestinal problems, sleep disturbance, and headaches. However, it must be considered that the patient would experience these effects from nicotine if they continued smoking anyway.

• Opioid antagonists, on the other hand, create severe side effects. This is because it requires a much higher dose of the drug to treat gambling than drug addiction. Correspondingly, the side effects are much worse. These include tiredness, anxiety, headaches, joint and muscle pains, cramps, and nausea.

• Side effects are a negative of drug therapy because they are hard on the patient and inhibit people from completing the entire course of treatment.

• Limited treatment/individual differences: Drug therapy is a limited treatment. Some addictions make addicts disorganised and unmotivated, i.e., they might forget to take their medication, making the treatment less effective.

• There are also individual differences that could affect the effectiveness of drug treatments. For instance, small genetic variations like the presence of a single gene can affect Naltrexone. Alcoholics with one variant of this gene responded much better to the drug than those that didn’t. Chung et al. (2012) suggest that drug treatments need to become more tailored to individual genetic profiles before they can be consistently effective.