Clinical Practice Guideline of Spanish Society of Pneumology and Thoracic Surgery (SEPAR) on Pharmacological Treatment of Tobacco Dependence 2023

INTRODUCTION

There are multiple systematic reviews and meta-analyses on the efficacy and safety of pharmacological treatments against nicotine dependence. However, there are few guidelines to answer frequent questions asked by a clinician treating a smoker. Therefore, the aim of this paper is to facilitate the treatment of tobacco addiction.

MATERIAL AND METHODS

12 PICO questions are formulated from a GLOBAL PICO question: "Efficacy and safety of pharmacological treatment of tobacco dependence". A systematic review was carried out to answer each of the questions and recommendations were made. The GRADE (Grading of Recommendations, Assessment, Development and Evaluation) system was used to grade the certainty of the estimated effects and the strength of the recommendations.

RESULTS

Varenicline, nicotine replacement therapy (NRT), bupropion and cytisine are more effective than placebo. Varenicline and combined nicotine therapy are superior to the other therapies. In smokers with high dependence, a combination of drugs is recommended, being more effective those associations containing varenicline. Other optimization strategies with lower efficacy consist of increasing the doses, the duration, or retreat with varenicline. In specific populations varenicline or NRT is recommended. In hospitalized, the treatment of choice is NRT. In pregnancy it is indicated to prioritize behavioral treatment. The financing of smoking cessation treatments increases the number of smokers who quit smoking. There is no scientific evidence of the efficacy of pharmacological treatment of smoking cessation in adolescents.

CONCLUSIONS

The answers to the 12 questions allow us to extract recommendations and algorithms for the pharmacological treatment of tobacco dependence.

Mechanism of action of dopaminergic agents in Parkinson's disease

As the substantia nigra degenerates in Parkinson's disease (PD), the nigrostriatal pathway is disrupted, reducing striatal dopamine and producing PD symptoms. Although dopamine does not readily cross the blood-brain barrier, its precursor, levodopa, does. Levodopa is absorbed in the small bowel and is rapidly catabolized by aromatic-L-amino-acid decarboxylase (AADC) and catechol-O-methyltransferase (COMT). Because gastric AADC and COMT degrade levodopa, the drug is given with inhibitors of AADC (carbidopa or benserazide), and inhibitors of COMT will also enter clinical use. Although the exact site of decarboxylation of exogenous levodopa to dopamine in the brain is unknown, most striatal AADC is located in nigrostriatal dopaminergic nerve terminals. Newly synthesized dopamine is stored in the terminals and then released, stimulating postsynaptic dopamine receptors and mediating the antiparkinsonian action of levodopa. Dopamine agonists act directly on postsynaptic dopamine receptors, thus obviating the need for metabolic conversion, storage, and release. How the actions of dopaminergic drugs produce side effects and how these side effects should be managed are discussed.