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Biomedical subjects

Douglas N Fish

Publications and source records attributed to Douglas N Fish.

At least 19 recordsLinked to original sources
PubMed2007

Enteral glutamine supplementation in critically ill patients with burn injuries: a retrospective case-control evaluation.

STUDY OBJECTIVES: To evaluate the clinical application of enteral glutamine supplementation in critically ill patients and compare the frequency of nosocomial infections in these patients with a historical control group in a burn intensive care unit (BICU), and to assess lengths of stay in the hospital and BICU, mortality rates, and safety profile of glutamine. DESIGN: Retrospective case-control descriptive study. SETTING: A university-affiliated hospital BICU. PATIENTS: Seventeen patients receiving enteral glutamine supplementation and 15 historical control patients who were admitted to the BICU for thermal burn injuries from January 1, 2001-September 30, 2004. MEASUREMENTS AND MAIN RESULTS: Data for patients receiving enteral glutamine supplementation were identified through the pharmacy database, and data for the control patients were identified through the BICU patient registry. No significant differences were noted in baseline characteristics or nutritional parameters and outcomes between the two groups. The mean daily dose and duration of glutamine were 0.52 g/kg and 21.6 days, respectively. The mean number of infections/patient between the glutamine and control groups was similar (2.47 and 2.73, respectively) as was the number of gram-negative infections (1.29 and 1.20, respectively). Bloodstream infections occurred more frequently in the glutamine group (24 vs 8 patients, p=0.0006); however, cellulitis (4 vs 11, p=0.05) and pneumonia (9 vs 15, p=0.15) occurred less often. For the glutamine group versus control group, BICU length of stay (17.9 vs 15.3 days, p=NS), hospital length of stay (32.3 vs 26 days, p=NS), and mortality rates (0% vs 6.7%, p=NS) were similar between groups. No adverse events were attributed to glutamine supplementation. CONCLUSION: Enteral glutamine supplementation was not associated with a change in the cumulative rate of infectious complications compared with the control group, but this was attributed to more cases of bloodstream infections and fewer cases of pneumonia and cellulitis in the glutamine group. Large, prospective, randomized trials designed to detect small but clinically relevant outcomes are needed to definitively determine the effect of enteral glutamine supplementation in the BICU population.

Adolescent↗
PubMed2006

Antimicrobial resistance: factors and outcomes.

Antimicrobial resistance in the ICU is characterized by increasing overall resistance rates among gram-negative and gram-positive pathogens and increased frequency of multidrug-resistant organisms. In addition to basic principles of appropriate drug selection for empiric and definitive therapy, other specific strategies that may decrease problems of resistance through improved use of antimicrobials include appropriate application of pharmacokinetic and pharmacodynamic principles to antimicrobial use, aggressive dosing of antimicrobials, use of broad-spectrum and combination antimicrobial therapy for initial treatment, decreased duration of antimicrobial therapy, hospital formulary-based antimicrobial restrictions, use of antimicrobial protocols and guidelines, programs for restriction of target antimicrobials, scheduled antimicrobial rotation, and use of antimicrobial management programs. Combinations of various approaches may offer the best potential for effectively intervening in and reducing the spread of resistant pathogens in critically ill patients.

Anti-Bacterial Agents↗
PubMed2006

Levofloxacin pharmacokinetics and pharmacodynamics in patients with severe burn injury.

Levofloxacin pharmacokinetics were studied in 11 patients with severe burn injuries. Patients (values are means +/- standard deviations; age, 41 +/- 17 years; weight, 81 +/- 12 kg; creatinine clearance, 114 +/- 40 ml/min) received intravenous levofloxacin at 750 mg (n = 10 patients) or 500 mg (n = one patient) once daily. Blood samples were collected on day 1 of levofloxacin therapy; eight patients were studied again on days 4 to 6. The pharmacodynamic probability of target attainment (PTA) was evaluated by Monte Carlo simulation. Mean systemic clearance, half-life, and area under the concentration-time curve over 24 h after levofloxacin at 750 mg were 9.0 +/- 3.2 liters/h, 7.8 +/- 1.6 h, and 93 +/- 31 mg . h/liter, respectively. There were no differences in pharmacokinetic parameters between day 1 and day 4; however, large intrapatient and interpatient variability was observed. Levofloxacin pharmacokinetics in burned patients were similar to those reported in other critically ill populations. Levofloxacin at 750 mg achieved >90% PTA for gram-negative and gram-positive pathogens with MICs of < or =0.5 microg/ml and MICs of < or =1 microg/ml, respectively. However, satisfactory PTA was not obtained with less-susceptible gram-negative organisms with MICs of 1 microg/ml or any organism with a MIC of > or =2 microg/ml. The results of this study indicate that levofloxacin should be administered at 750 mg/day for treatment of systemic infections in severely burned patients. However, even 750 mg/day may be inadequate for gram-negative organisms with MICs of 1 to 2 microg/ml even though they are defined as susceptible. Alternative antibiotics or treatment strategies should be considered for infections due to these pathogens.

Adult↗
PubMed2006

Evaluation of bivalirudin treatment for heparin-induced thrombocytopenia in critically ill patients with hepatic and/or renal dysfunction.

STUDY OBJECTIVE: To evaluate the safety, effectiveness, and dosing of bivalirudin for treatment of heparin-induced thrombocytopenia (HIT) in critically ill patients with hepatic and/or renal dysfunction. DESIGN: Retrospective cohort study. SETTING: University-affiliated medical center PATIENTS: Eighteen patients older than 18 years who were admitted to the intensive care unit (ICU), had hepatic and/or renal dysfunction, and were treated with bivalirudin for the diagnosis of HIT between January 1, 2004, and March 31, 2005. MEASUREMENTS AND MAIN RESULTS: Patient records were reviewed for dosage and duration of bivalirudin therapy, occurrence of thrombosis, and clinically significant adverse effects. Of the 18 patients identified, 12 had both hepatic and renal dysfunction (group 1), four had hepatic dysfunction (group 2), and two had renal dysfunction (group 3). Demographics were similar among the groups. Mean +/- SD age was 54 +/- 15 years and weight was 82 +/- 14 kg, 67% were male, 83% were Caucasian, and 56% were receiving renal replacement therapy. Mean bivalirudin doses were 0.06 +/- 0.15 mg/kg/hour (median 0.03 mg/kg/hr), 0.14 +/- 0.05 mg/kg/hour (median 0.14 mg/kg/hr), and 0.05 +/- 0.01 mg/kg/hour (median 0.05 mg/kg/hr) for patients in groups 1, 2, and 3, respectively. Ten patients receiving continuous venovenous hemofiltration with or without dialysis received a mean dose of 0.04 +/- 0.03 mg/kg/hour (median 0.03 mg/kg/hr). In the 18 patients, mean bivalirudin duration was 15 +/- 17 days, activated partial thromboplastin time (aPTT) was 69 +/- 22 seconds, and international normalized ratio was 2.2 +/- 0.8. Supratherapeutic aPTTs were most common on days 1 (22%) and 2 (28%) when bivalirudin doses were highest. Clinically significant bleeding did not occur in any patient. Thrombosis occurred in one patient (6%) while receiving bivalirudin. CONCLUSION: Patients in the ICU who have hepatic and/or renal dysfunction require low doses of bivalirudin to achieve aPTT values 1.5-2.5 times baseline. Bivalirudin can be safely started at 0.14 mg/kg/hour in patients with hepatic dysfunction, 0.03-0.05 mg/kg/hour in those with renal or combined hepatic and renal dysfunction, and 0.03-0.04 mg/kg/hour in patients receiving continuous renal replacement therapy.

Adult↗
PubMed2005

Vasopressin, not octreotide, may be beneficial in the treatment of hepatorenal syndrome: a retrospective study.

BACKGROUND: Hepatorenal syndrome (HRS) is a severe complication of cirrhosis and is associated with high mortality. Ornipressin and terlipressin are effective in treatment of HRS, but are not available in the USA. The efficacy of vasopressin (AVP) and octreotide (OCT) infusions, commonly utilized in the USA, in the treatment of HRS is unknown. This study aims to evaluate the effects of AVP and OCT on renal function, systemic haemodynamics and clinical outcomes in HRS. METHODS: This observational study evaluated patients receiving AVP or OCT therapy for HRS from January 2000 to December 2003. Recovery from HRS was defined as a decrease in the serum creatinine (SCr) to a value < or =1.5 mg/dl. RESULTS: Forty-three patients were identified: eight received AVP, 16 received OCT and 19 received both AVP and OCT. Patients who received AVP alone or in combination with OCT had significantly greater recovery rates than those receiving OCT monotherapy (42 vs 38 vs 0%, respectively, P = 0.01). The average time to response in serum creatinine (SCr) was 7+/- 2 days. The mean AVP doses were 0.23+/-0.19 U/min in patients demonstrating clinical response. Therapy with AVP was an independent predictor of recovery (odds ratio 6.4, 95% confidence interval 1.3-31.8). Patients who responded to therapy had significantly lower mortality (23 vs 67%, P = 0.008) and higher rates of liver transplantation (23 vs 0%, P = 0.005). No adverse effects related to AVP therapy were observed. CONCLUSION: When compared with OCT, HRS patients treated with AVP had significantly higher recovery rates, improved survival and were more likely to receive a liver transplant.

Antidiuretic Agents↗
PubMed2005

Pharmacokinetics and pharmacodynamics of imipenem during continuous renal replacement therapy in critically ill patients.

The pharmacokinetics of imipenem were studied in adult intensive care unit (ICU) patients during continuous venovenous hemofiltration (CVVH; n=6 patients) or hemodiafiltration (CVVHDF; n=6 patients). Patients (mean+/-standard deviation age, 50.9+/-15.9 years; weight, 98.5+/-15.9 kg) received imipenem at 0.5 g every 8 to 12 h (total daily doses of 1 to 1.5 g/day) by intravenous infusion over 30 min. Pre- and postmembrane blood (plasma) and corresponding ultrafiltrate or dialysate samples were collected 1, 2, 4, and 8 or 12 h (depending on dosing interval) after completion of the drug infusion. Drug concentrations were measured using validated high-performance liquid chromatography methods. Mean systemic clearance (CL(S)) and elimination half-life (t1/2) of imipenem were 145+/-18 ml/min and 2.7+/-1.3 h during CVVH versus 178+/-18 ml/min and 2.6+/-1.6 h during CVVHDF, respectively. Imipenem clearance was substantially increased during both CVVH and CVVHDF, with membrane clearance representing 25% and 32% of CL(S), respectively. The results of this study indicate that CVVH and CVVHDF contribute to imipenem clearance to a greater degree than previously reported. Imipenem doses of 1.0 g/day appear to achieve concentrations adequate to treat most common gram-negative pathogens (MIC up to 2 microg/ml) during CVVH or CVVHDF, but doses of 2.0 g/day or more may be required to adequately treat and prevent resistance in pathogens with higher MICs (MIC=4 to 8 microg/ml). Higher doses should only be used after consideration of potential central nervous system toxicities or other risks of therapy in these severely ill patients.

Adult↗
PubMed2005

Nosocomial infections due to multidrug-resistant Pseudomonas aeruginosa: epidemiology and treatment options.

Pseudomonas aeruginosa is one of the leading gram-negative organisms associated with nosocomial infections. The increasing frequency of multi-drug-resistant Pseudomonas aeruginosa (MDRPA) strains is concerning as efficacious antimicrobial options are severely limited. By searching MEDLINE from January 1966-February 2005 and relevant journals for abstracts, we reviewed the frequency, risk factors, and patient outcomes of MDRPA nosocomial infections in critically ill patients, determined the available antimicrobial therapies, and then provided recommendations for clinicians. The definition of MDRPA was established as isolates intermediate or resistant to at least three drugs in the following classes: beta-lactams, carbapenems, aminoglycosides, and fluoroquinolones. Reported rates of MDRPA varied from 0.6-32% according to geographic location and type of surveillance study. Risk factors for MDRPA infection included prolonged hospitalization, exposure to antimicrobial therapy, and immunocompromised states such as human immunodeficiency virus infection. Emergence of MDRPA isolates during therapy was reported in 27-72% of patients with initially susceptible P. aeruginosa isolates. Patients with severe MDRPA infections should be treated with combination therapy, consisting of an antipseudomonal beta-lactam with an aminoglycoside or fluoroquinolone rather than aminoglycoside and fluoroquinolone combinations, to provide adequate therapy and improve patient outcomes. Synergy has been observed when resistant antipseudomonal drugs were combined in vitro against MDRPA with successful clinical application reported in two centers. Colistin with adjunctive therapy, such as a beta-lactam or rifampin, may be a useful agent in MDRPA when antimicrobial options are limited, but patients should be monitored closely for toxicities associated with this agent. Standardization of terminology for MDRPA isolates is needed for consistency and comparability of surveillance and institutional reports. Clinical studies are needed to identify risk factors for MDRPA development and to determine the economic impact of these infections, as well as to determine the most efficacious antimicrobial regimens and duration of therapy to maximize outcomes in the treatment of MDRPA infections.

Anti-Bacterial Agents↗
PubMed2005

Evaluation of diagnostic tests and argatroban or lepirudin therapy in patients with suspected heparin-induced thrombocytopenia.

STUDY OBJECTIVES: To evaluate diagnostic tests for heparin-induced thrombocytopenia (HIT), a serious drug reaction that can occur in patients receiving heparin, and to evaluate treatment with direct thrombin inhibitors-the only initial drug therapy that decreases the risk of thromboembolism associated with immune-mediated HIT. DESIGN: Retrospective cohort study. SETTING: University teaching hospital. SUBJECTS: Patients with HIT treated with argatroban or lepirudin between January 1, 2000, and December 31, 2003. MEASUREMENTS AND MAIN RESULTS: Patients were assessed for dosage and duration of argatroban or lepirudin therapy, HIT diagnostic tests, and clinically significant adverse events. Thirty-four patients received argatroban, 42 received lepirudin. Mean+/-SD doses of argatroban and lepirudin were 1.2+/-0.9 microg/kg/minute and 0.09+/-0.11 mg/kg/hour, respectively; both were 40% lower than the recommended doses. Mean duration of therapy was 10+/-9 days. Supratherapeutic activated partial thromboplastin times were observed in 30 (39%), 10 (13%) , and six (8%) of 76 patients on days 1, 2, and 3, respectively (p<0.0001). Clinically significant bleeding occurred in 6% of patients receiving argatroban and in 5% of those receiving lepirudin (p=0.99); all patients had an activated partial thromboplastin time of longer than 100 seconds. Although platelet-aggregation tests were ordered in 55 (72%) of 76 patients, they were not useful in 16 (29%) because of equivocal or contradictory results. CONCLUSION: Due to supratherapeutic activated partial thromboplastin times, our patients often required doses of argatroban and lepirudin lower than those usually recommended. Thus, direct thrombin inhibitors should be started at low initial doses and titrated to target activated partial thromboplastin times to achieve appropriate efficacy and to avoid increasing the risk of bleeding. Platelet-aggregation tests were least useful for evaluating HIT. Appropriate diagnostic strategies should be used to avoid unnecessary drug use.

Anticoagulants↗
PubMed2004

Effects of continuous vasopressin infusion in patients with septic shock.

BACKGROUND: Small studies have reported that vasopressin improves hemodynamic instability in patients with septic shock. OBJECTIVE: To determine whether vasopressin infusion increases blood pressure, decreases catecholamine vasopressor use, and improves renal function in a large patient population with septic shock when used in a clinical setting. METHODS: A retrospective chart audit was conducted of critically ill patients who received vasopressin infusion for septic shock from January 2000 through September 2002. Demographic, hemodynamic, laboratory, vasopressor, and adverse event data were collected. Statistical methods included ANOVA with Tukey's test for post hoc analysis. RESULTS: A total of 102 of 353 patients met study criteria. The mean +/- SD vasopressin dosage regimen was 0.11 +/- 0.17 units/min for 53.8 +/- 71.5 hours. Compared with baseline, vasopressin infusion improved mean arterial pressure (MAP) by 15% within one hour (p < 0.05), reduced heart rate by 9% within 4 hours (p < 0.05), and reduced hourly dopamine dosage by 25% within 8 hours (p < 0.05). These effects persisted through 96 hours. Other hemodynamic variables and catecholamine vasopressor usage parameters were not statistically different from baseline. Urine output, serum creatinine, and serum sodium concentrations were not statistically changed from baseline. Adverse events possibly associated with vasopressin infusion included ischemic digits/extremities, myocardial infarction, and hyponatremia. CONCLUSIONS: Vasopressin infusion was effective in increasing MAP and reducing heart rate while decreasing the dopamine dosage in patients with septic shock. Comparative studies with catecholamine vasopressors are needed to define the optimal role of vasopressin in septic shock therapy. In the meantime, vasopressin infusion at <or=0.03 units/min should be considered only if response to 1 or 2 catecholamine vasopressors is inadequate or as a method to reduce the dose of these therapies.

Blood Pressure↗
PubMed2004

National surveillance of antimicrobial resistance in Pseudomonas aeruginosa isolates obtained from intensive care unit patients from 1993 to 2002.

Nosocomial infections caused by Pseudomonas aeruginosa in critically ill patients are often difficult to treat due to resistance to multiple antimicrobials. The purpose of this study was to evaluate antimicrobial resistance among P. aeruginosa isolates from intensive care unit patients in the United States from 1993 to 2002 by using the Intensive Care Unit Surveillance Study database. Over the 10-year period, susceptibility of 13,999 nonduplicate isolates of P. aeruginosa was analyzed. From 1993 to 2002, nationwide increases in antimicrobial resistance were greatest for ciprofloxacin, imipenem, tobramycin, and aztreonam. Rates of multidrug resistance (resistance to > or =3 of the following drugs: ceftazidime, ciprofloxacin, tobramycin, and imipenem) increased from 4% in 1993 to 14% in 2002. The lowest dual resistance rates were observed between aminoglycosides or fluoroquinolones with piperacillin-tazobactam while the highest were for those that included beta-lactams and ciprofloxacin. Ongoing surveillance studies are crucial in monitoring antimicrobial susceptibility patterns and selecting empirical treatment regimens.

Drug Resistance, Multiple, Bacterial↗
PubMed2004

Synergistic activities of moxifloxacin combined with piperacillin-tazobactam or cefepime against Klebsiella pneumoniae, Enterobacter cloacae, and Acinetobacter baumannii clinical isolates.

The bactericidal activity of moxifloxacin alone and in combination with cefepime or piperacillin-tazobactam against clinical isolates of Klebsiella pneumoniae, Enterobacter cloacae, and Acinetobacter baumannii was evaluated by using time-kill methods and antimicrobial concentrations of one-half and one times the MIC. Synergy was observed in 58 to 88% of the strains and resulted in bactericidal activity against 60 to 100% of the strains. Combinations including moxifloxacin demonstrated enhanced bactericidal activity compared with that of either agent tested alone.

Acinetobacter Infections↗
PubMed2004

The role of vasopressin in vasodilatory septic shock.

Septic shock that requires therapy with adrenergic agents is associated with high rates of mortality. Inappropriately normal or low serum concentrations of vasopressin contribute to the development of hypotension during sepsis. We critically evaluated the role of administering exogenous vasopressin to patients with septic shock. A computerized search of MEDLINE from January 1966--December 2003 and a manual search of relevant journals for abstracts were conducted. Eleven retrospective, six prospective cohort, and four prospective randomized studies were identified. Most studies evaluated short-term infusions of vasopressin at 0.08 U/minute or less as add-on therapy in patients requiring adrenergic agents. The results show that starting vasopressin in patients with septic shock increases systemic vascular resistance and arterial blood pressure, thus reducing the dosage requirements of adrenergic agents. These effects are rapid and sustained. Substantial enhancement of urine production, likely due to increased glomerular filtration rate, was shown in several studies. A few studies demonstrated clinically significant reduced cardiac output or cardiac index after vasopressin was begun, necessitating cautious use in patients with cardiac dysfunction. Vasopressin was associated with ischemia of the mesenteric mucosa, skin, and myocardium; elevated hepatic transaminase and bilirubin concentrations; hyponatremia; and thrombocytopenia. Limiting the dosage to 0.03 U/minut or less may minimize the development of these adverse effects. Vasopressin 0.03 U/minute or less should be considered if response to one or two adrenergic agents is inadequate or as a method to reduce the dosage of adrenergic agents. At present, vasopressin therapy should not be started as first-line therapy. Additional studies are needed to determine the optimum dosage, duration, and place in therapy of vasopressin relative to adrenergic agents. A multicenter, comparative study of vasopressin 0.03 U/minute as add-on therapy is under way and should provide mortality data.

Adult↗
PubMed2003

Assessing renal function in cirrhotic patients: problems and pitfalls.

Assessment of glomerular filtration rate (GFR) by common creatinine-based methods potentially is very inaccurate in patients with cirrhosis. Cirrhotic patients have several underlying conditions that contribute to falsely low serum creatinine concentrations, even in the presence of moderate to severe renal impairment, and often cause creatinine-based methods to overestimate true GFR. Such underlying conditions include decreased creatinine production secondary to decreased hepatic creatine synthesis, increased tubular creatinine secretion, and decreased skeletal muscle mass. These factors all contribute to serum creatinine concentrations that often do not accurately reflect renal function. Serum creatinine level, measured creatinine clearance, and calculated creatinine clearance may all significantly overestimate GFR; the degree of GFR overestimation was a median of 95% in published studies. Until more accurate methods of estimating GFR in cirrhotic patients are adequately validated, care should be exercised in the management of these patients because of the potential for severely impaired renal function, even in the face of normal serum creatinine concentrations.

Glomerular Filtration Rate↗
PubMed2003

Levofloxacin: update and perspectives on one of the original 'respiratory quinolones'.

The fluoroquinolone class of antimicrobials has enjoyed enormous clinical and marketing success over the past 20 years. These drugs have proven to be extremely useful in a broad range of clinical indications including both common community-acquired as well as nosocomial bacterial infections. Levofloxacin (Levaquin, Tavanic), like ciprofloxacin (Cipro), has established an enviable record of safe and efficacious use, and in many ways has become the agent against which all of the newer fluoroquinolones are judged. New clinical indications in complicated skin and skin structure infections, nosocomial pneumonia and chronic bacterial prostatitis continue to expand the important role of this already versatile drug. In addition, the use of 'short-course, high-dose' therapies are being studied in indications, such as community-acquired pneumonia, in an effort to optimize the efficacy and convenience of the drug while minimizing the future development of resistance. As the use of levofloxacin continues to expand, future challenges will include the threat of increasing antimicrobial resistance and the availability of newer alternative agents, both newer fluoroquinolones as well as agents of other antibiotic classes.

Animals↗
PubMed2002

Optimal antimicrobial therapy for sepsis.

The selection of appropriate antimicrobial therapy for patients with sepsis is discussed. Antimicrobial selection is based on the most likely source of infection, the most common pathogens at that site, knowledge of antimicrobial susceptibility patterns in the local community and institution, and host factors. Prompt initiation of appropriate antimicrobial therapy is essential for achieving the best possible outcomes. Defining optimal antimicrobial therapy for sepsis is difficult because few clinical studies have specifically addressed this. Sepsis has traditionally been associated with gram-negative infections, but studies indicate that gram-positive pathogens commonly cause sepsis and are associated with high mortality. Enterobacteriaceae, species, Pseudomonas aeruginosa, and Staphylococcus aureus are the most common pathogens in sepsis patients and should be considered in the selection of empirical therapy. Antimicrobial therapy should be initiated as soon as samples have been obtained for culture; empirical therapy should cover a very broad spectrum of organisms, with consideration given to the most likely pathogens for the infection site. An antipseudomonal beta-lactam with or without an aminoglycoside is recommended for initial therapy in most patients. The role of monotherapy versus combination therapy is controversial. Routine use of vancomycin and antifungal therapy as part of initial regimens should be discouraged but may be justified in specific circumstances.

Anti-Bacterial Agents↗
PubMed2002

Acyclovir concentrations in human breast milk after valaciclovir administration.

OBJECTIVE: The purpose of this study was to determine the valaciclovir and acyclovir pharmacokinetic profiles in serum and breast milk after valaciclovir administration to women after delivery. STUDY DESIGN: Valaciclovir (500 mg twice daily for 7 days) was given to 5 women after delivery who were breast-feeding healthy term infants. Matched serum and breast milk samples were obtained after the initial dose, on day 5 and 24 hours after the drug was discontinued. Infant urine was obtained on day 5. RESULTS: Valaciclovir was rapidly converted to acyclovir. The peak serum acyclovir concentration occurred 3 hours before the peak breast milk concentration (2.7 microg/mL at 1 hour vs 4.2 microg/mL at 4 hours). The serum acyclovir elimination half-life was 2.3 hours. The ratio of breast milk to serum acyclovir concentration was highest 4 hours after the initial dose at 3.4 and reached steady state ratio at 1.85. The median infant urine acyclovir concentration at steady state was 0.74 microg/mL. CONCLUSION: Valaciclovir is rapidly converted to acyclovir and concentrates in breast milk. However, the amount of acyclovir in breast milk after valaciclovir administration is considerably less (2%) than that used in therapeutic dosing of neonates.

Acyclovir↗