Pharmacovigilance is important in monitoring the occurrence and prevention of adverse drug reactions. The use of Warning letter is a way to attract the attention of the doctors, but also the obligation to limit and/or warn about the use of the drug in certain conditions and comorbidities. Quinolones and fluoroquinolones are an important group of antibiotics that, due to their efficiency and good compliance, are often used in the treatment of various infections. Indications for the use of fluoroquinolones include infections of the respiratory tract, ear, throat and nose, invasive otitis externa caused by Pseudomonas aeruginosa, infections of the urinary tract, skin and soft tissues, bones, joints, pelvic organs, gastrointestinal infections, eradication of Salmonella germs and severe systemic infections. In order to ensure the safe use of fluoroquinolones in patients, and according to the announcements of ALIMS, based on the evidence of other drug agencies (e.g. European Medicines Agency - EMA and others), the prescription of fluoroquinolones should be prohibited for patients who have had aortic dissection (absolute risk). Patients at risk of aortic aneurysm and dissection are at relative risk and should be allowed fluoroquinolones after benefit-risk assessment and consideration of other therapeutic options. This group would also include patients with predisposing conditions for the occurrence and development of aneurysms (aneurysmal disease in family history, earlier occurrence of aneurysm or aortic dissection, Marfan syndrome, vascular form of Ehlers-Danlos syndrome, Takayasu's arteritis, giant cell arteritis of the arteries, Behçet's disease, hypertension and atherosclerosis), as well as patients with congenital or existing heart valve disease, connective tissue disorder (Marfan syndrome or Ehlers-Danlos syndrome), Turner syndrome, Behçet's disease, hypertension, rheumatoid arthritis and infective endocarditis. For all other infections with/or without comorbidities, prescribing fluoroquinolone can be as common as for other antibiotics, following antibiotic prescribing recommendations according to current national and other guidelines, with suggestions given in the "Summary of Drug Characteristics" and "Medication Instructions".