Tobacco is one of the most legally used substances with psychoactive effects since its discovery. Even though smoking is now banned in establishments and enclosed public spaces and its price has risen through taxation, millions of people still have the habit of smoking.

But many of these people, at some point, need to stop. While it is possible to do so on a voluntary basis, in some cases they may need psychological and even pharmacological help. In the latter case, one of the existing drugs used in smoking cessation is bupropion, a drug originated as an antidepressant .

What is bupropion?

Bupropion is a well-known antidepressant, although it is more common and distinctive than its application for depression because of its effectiveness in the treatment of tobacco addiction . In this sense, it is a treatment that does not include nicotine and that is recommended together with some type of therapy or psychological treatment. This shows that psychotropic drugs are not designed following a plan from 0, but that in their development there is a certain process of trial and error, and that sometimes utilities arise for the drug that at first had not even been taken into account.

Bupropion is a specific inhibitor of the reuptake of dopamine and noradrenaline, or NRTI , which works by increasing the levels of these neurotransmitters in the brain. Compared to other drugs in the antidepressant group, bupropion has the advantage of not generating sexual dysfunction, although on the other hand its effectiveness alone seems lower compared to other drugs on the market.

Thus, bupropion is an example that molecules related to other substances used for a certain kind of disorder may be more useful in different health disorders, no matter how similar their structure is.

Mechanism of action

Bupropion’s functioning and mechanism of action is based on its role as a selective dopamine and noradrenaline reuptake inhibitor. This implies that bupropion acts by preventing these two transmitters (associated with gratification and energy) from being recaptured by the presynaptic neuron, so that they are available to post-synaptic neurons for longer. In addition, it appears to stimulate the secretion of these neurotransmitters. Thus, dopamine and noradrenaline levels and their transport increase at the brain level, which can alter mood .

It has also been found to have an effect at the acetylcholine level, binding to nicotine receptors and exerting an uncompetitive antagonistic effect. Although there is no certainty of this, this element is one of the possible explanations for its role in smoking cessation.

However, it should be noted that the exact way in which the mechanism of action of bupropion and psychotropic drugs in general works is still unknown. Its use does not guarantee that it will work to relieve the symptoms of the disorder being treated, and in fact its efficacy is only slightly better than that of placebo. That does not mean that in many cases it is not very useful, simply that the percentage of patients who try this treatment and do not obtain any benefit is relatively high.

Indications: uses in disorders

Bupropion is a drug that throughout its history has had several uses. Although it was born as an antidepressant and is still sometimes used to treat this condition both as monotherapy (single therapy) and as a combination therapy (more commonly, to boost specific antidepressants when first-choice drugs are not effective), the fact is that on its own it is generally considered less effective than other antidepressants .

The most outstanding and most widely used use of this drug is in smoking cessation, resulting in the reduction of the consumption habit and the desire to smoke. In this sense, its mechanism of action seems to contribute to the cessation of craving (possibly due on the one hand to its nicotinic receptor antagonism and its interaction with cerebral dopamine, although the exact mechanism is not fully known). Another disorder in which it is used is seasonal affective disorder, in which depressive episodes appear associated with certain times of the year.

In addition to the above it has sometimes been used in the treatment of bipolar disorder , especially during the depressive episodes that can occur in this disorder (although this use requires caution as there is a risk of turning the disorder into a manic crisis). Also in ADHD. But in any case, more research is needed and the existence of possible risks must be taken into account.

Side effects

Bupropion is a drug that is very useful in smoking cessation and is used in cases of depression, but as with the other drugs its clinical usefulness is not free of risks and possible side effects .

This is because the active ingredient in bupropion affects many areas of the body, not just the areas that might produce an improvement in symptoms. This undesirable interaction generates a chain reaction of somewhat unpredictable consequences, which can lead to further health problems (although these usually disappear as the substance leaves the body). Therefore, its use should always be monitored and indicated by physicians.

In this sense, among the main side effects of bupropion we can find the cause of insomnia (being among the most frequent), dry mouth and dizziness, headaches, nausea, constipation, tachycardia, tremors, skin rashes, agitation and nervousness. It can also cause a decrease in appetite.

In more serious cases it can generate convulsions (this being one of the most known serious risks), arrhythmias, hallucinations, panic or difficulties in breathing or feeding, or inflammations, making it necessary to see a doctor. In some cases it can cause irritability, hostility, depression, and thoughts of suicide.

Contraindications

In addition to these side effects, this drug is totally contraindicated in some population groups . People who are allergic to this drug or any of its components (something that is otherwise obvious), those who take certain medications (especially MAOIs), dependence on substances beyond tobacco (such as alcohol, drugs and medicines) and those who suffer from epilepsy, brain tumors and anorexia nervosa or bulimia (since it reduces appetite) should not take this drug.

It is also not recommended, although it can sometimes be used if the benefits are considered greater than the risks, in cases of people with kidney or liver failure, head trauma, insomnia, or consumption of other medications that may interact with bupropion.

Diabetics, alcoholics, hypertensive patients or people with psychiatric disorders (since it may contribute to the appearance of mania in bipolars or psychotic crises in schizophrenia, among others) also have it contraindicated (or at least the treatment should be done with a high level of control of the patient’s condition and the doses administered) due to the risk of the appearance of convulsions and other side effects. Finally, it is also not recommended for pregnant and lactating women.

Price

The price of bupropion, for a box of 30 tablets of 150 milligrams , is about 26 euros in Spain and 1400 Mexican pesos in Mexico, approximately. In any case, it should be taken under medical supervision, since its effects are too powerful to be taken without the supervision of specialists.

Bibliographic references:

  • Dale, L.C.; Glover, E.D.; Sachs, D.P.L.; Schroeder, D.R.; Offord, K.P.; Croghan, I.T. & Hurt, R.D. (2001). Bupropion for smoking cessation. Chest, 119:1357-64.
  • Grossberg, George T.; Kinsella, Laurence J. (2018). Clinical psychopharmacology for neurologists: a practical guide. Springer. pp. 45 – 71.
  • Johnston, A.J., Ascher, J., Leadbetter, R., Schmith, V.D., Patel, D.K., Durcan, M., Bentley, B. (2002). Pharmacokinetic optimisation of sustained-release bupropion for smoking cessation. Drugs. 62 Suppl 2: pp. 11 – 24.
  • Patel, K., Allen, S., Haque, M.N., Angelescu, I., Baumeister, D., Tracy, D.K. (2016). Bupropion: a systematic review and meta-analysis of effectiveness as an antidepressant. Therapeutic Advances in Psychopharmacology. 6 (2): 99–144.
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