The prevalence of hypotonia in patients on continuous ambulatory peritoneal dialysis (CADO) is about 12%, and its pathophysiology is complex. The study presents a case of a patient on CADO, whose episodes of low blood pressure may be associated with the use of antibiotic amikacine (group of aminoglycosides). Female, aged 68, was admitted to the Clinic for CADO treatment of the renal failure. In the first week after the catheter implantation the patient complained of dysuric symptoms. Due to significant E. coli bacteriuria 250 mg amikacine and 1 g cefazolin was introduced according to antibiogram. In the third day of antibioticotherapy the patient fainted with the blood pressure of 90/60 mm Hg. In the following days the patient presented blood pressure falls to the values of 90/60–80/50 mm Hg 2- or 3-times a day. The patient was feeling ill. All anti-hypertensives were stopped. In the repeated urinalysis leukocyturia was not found. Two days following the cessation of antibiotics patient’s state improved and the episodes of hypotonia disappeared. Blood pressure values increased and amlodipine and perindopril treatment was introduced in previously used doses. The mechanism of the hypotensive effect of aminoglycosides remains unclear. One of the hypotheses assumes that aminoglycosides are one of ligands with the affinity to bind at calcium receptor and may influence the parathormone (PTH) and parathyroid hypertensive factor (PHF) via this path. The hypotensive effect could be indirectly associated with the lowered membrane calcium concentration. The blood pressure fall observed after intravenous administration of amikacine may be with high probability associated with calcimimetric operation of the aminoglycoside and simultaneous PHF inhibition.