zithromax and Renal-Insufficiency

The bioavailability of azithromycin is approximately 37%. Concomitant administration of oral azithromycin with food significantly decreases by 50% drug bioavailability. Following a single oral 500 mg dose, peak plasma concentrations of about 0.35-0.45 mg/l are attained within approximately 2 hours. With a 500 mg oral dose on day 1, followed by 250 mg daily on days 2 to 5, peak and through plasma concentrations on day 5 are around 0.25 and 0.05 mg/l respectively. These low plasma concentrations are the consequence of extensive and rapid distribution from plasma to tissues. Plasma protein binding is low, less than 50% at plasma concentrations obtained with the usual dosage regimen. Apparent volume of distribution is very large, 25 to 35 l/kg. Azithromycin is mainly eliminated unchanged in the faeces via biliary excretion and transintestinal secretion. Urinary excretion is a minor elimination route: about 6% and an oral dose and 12% of an intravenous dose are recovered unchanged in urine. The mean terminal elimination half-life of azithromycin is 2 to 4 days. The pharmacokinetics of azithromycin is not significantly altered in elderly subjects and in patients with mild to moderate renal or hepatic insufficiency.

Topics: Administration, Oral; Adult; Age Factors; Aged; Aged, 80 and over; Anti-Bacterial Agents; Azithromycin; Humans; Infusions, Intravenous; Liver Failure; Reference Values; Renal Insufficiency

Azithromycin is an antibiotic with QT-prolonging potential commonly prescribed to individuals receiving hemodialysis. Hemodialysis patients have a high prevalence of clinical conditions, such as structural heart disease, that can enhance the pro-arrhythmic effects azithromycin, but were excluded from prior investigations evaluating the cardiac safety of azithromycin. Using data from the United States Renal Data System (2007-2017), we conducted two cohort studies to examine the cardiac safety of azithromycin relative to amoxicillin-based antibiotics (amoxicillin, amoxicillin/clavulanic acid) and levofloxacin (a fluoroquinolone antibiotic known to prolong the QT-interval) in the hemodialysis population. The primary outcome was five-day sudden cardiac death. Using inverse probability of treatment weighted survival models, we estimated hazard ratios, risk differences, and 95% confidence intervals. The azithromycin vs. amoxicillin-based antibiotic cohort included 282,899 patients and 725,431 treatment episodes (381,306 azithromycin and 344,125 amoxicillin-based episodes). Azithromycin vs. amoxicillin-based antibiotic treatment was associated with higher relative and absolute risks of sudden cardiac death, weighted hazard ratio of 1.70 (95% Confidence Interval, 1.36 to 2.11) and weighted risk difference per 100,000 treatment episodes of 25.0 (15.5 to 36.5). The azithromycin vs. levofloxacin cohort included 245,143 patients and 554,557 treatment episodes (387,382 azithromycin and 167,175 levofloxacin episodes). Azithromycin vs. levofloxacin treatment was associated with lower relative and absolute risks of sudden cardiac death, weighted hazard ratio of 0.79 (0.64 to 0.96) and weighted risk difference per 100,000 treatment episodes of -18.9 (-35.5 to -3.8). Thus, when selecting among azithromycin, levofloxacin, and amoxicillin-based antibiotics, clinicians should weigh the relative antimicrobial benefits of these drugs against their potential cardiac risks.

Topics: Amoxicillin; Amoxicillin-Potassium Clavulanate Combination; Anti-Bacterial Agents; Azithromycin; Death, Sudden, Cardiac; Fluoroquinolones; Humans; Levofloxacin; Renal Dialysis; Renal Insufficiency; United States

Ureaplasma urealyticum is a bacterial species correlated with urethritis in healthy individuals and invasive infections in immunocompromised patients. We describe a 20-year-old female with a history of remote heart transplant on everolimus, mycophenolate, and rituximab presenting with progressive urinary tract symptoms, renal failure, and neurologic symptoms. An extensive workup ultimately identified U urealyticum infection, and the patient successfully recovered after a course of azithromycin and doxycycline.

Topics: Anti-Bacterial Agents; Azithromycin; Doxycycline; Dysuria; Female; Humans; Immunocompromised Host; Male; Nervous System Diseases; Pyelonephritis; Renal Insufficiency; Ureaplasma Infections; Ureaplasma urealyticum; Young Adult

Topics: Aged; Anti-Bacterial Agents; Azithromycin; Community-Acquired Infections; Electrocardiography; Female; Humans; Pneumonia; Renal Insufficiency

HIV infections are a growing concern in the elderly as a result of improvements in therapeutics and monitoring, which have extended the life span for this HIV-infected population. Elderly patients potentially are more complicated to treat than younger HIV-infected individuals because of comorbidities and the physiological effects of aging on pharmacokinetics and pharmacodynamics. The patient, a 67-year-old African-American HIV-infected male, presents to the transitional care unit of university-affiliated hospital refusing to take medications and undergo laboratory testing, including blood draws. This patient's treatment is further complicated by poor renal function, medications with potential interactions, and a recent diagnosis of depression. This case demonstrates treatment and monitoring of an elderly patient with HIV and reveals the complications associated with this disease state. Specifically, it identifies nonadherence to medications and a lack of laboratory results, which affect the efficacy of treatment and monitoring, medication adjustments based on metabolism and renal excretion, monitoring of adverse effects of HIV and antiretroviral therapy, and comorbid conditions that may be linked to HIV and antiretroviral therapy such as depression and bone disease. Education on HIV medications, monitoring, and standards of care for pharmacists working with the geriatric population is warranted and should be emphasized as the HIV-infected elderly population continues to grow.

Topics: Aged; AIDS-Related Opportunistic Infections; Anti-HIV Agents; Antihypertensive Agents; Azithromycin; CD4 Lymphocyte Count; Depressive Disorder; Diltiazem; Drug Interactions; Drug Monitoring; HIV Infections; Humans; Hypertension; Lopinavir; Male; Patient Compliance; Pharmacists; Renal Insufficiency; Trimethoprim, Sulfamethoxazole Drug Combination; Zidovudine

Topics: Adult; Azithromycin; Cyclosporine; Drug Synergism; Drug Therapy, Combination; Female; Humans; Kidney Transplantation; Renal Insufficiency