Mycophenolate Aciclovir

MYCOPHENOLATE ANTIVIRALS -ACICLOVIR, GANCICLOVIR t plasma concentrations of both drugs. Toxic effects of both drugs likely Attributed to competition for renal tubular excretion Monitor blood counts - For signs and symptoms of immunosuppression, see Oinical Features of Some Adverse Drug Interactions, Immunosuppression and blood dyscrasias... 

MYCOPHENOLATE ANTIVIRALS-ACICLOVIR, GANCICLOVIR Possible T efficacy Competition for renal excretion Monitor renal function, particularly if on >4g valacidovir. 1 dose of acidovir if there is a background of renal failure... 

ACICLOVIR/ VALACICLOVIR ANTICANCER AND IMMUNOMODULATING DRUGS- 1. CICLOSPORIN 2. MYCOPHENOLATE 3. TACROLIMUS 1.1 nephrotoxicity 2. Possible T efficacy 3. t levels with protease inhibitors 1. Additive side-effect 2. Competition for renal excretion 3. Inhibition of CYP3A4-mediated metabolism of tacrolimus 1. Monitor renal function prior to concomitant therapy and monitor cidosporin levels 2. Monitor renal function particularly if on >4g valaciclovir 1 dose of aciclovir if there is a background of renal failure 3. Monitor clinical effects closely check levels... 

A retrospective study in 19 children with renal transplants identified three who developed disseminated varicella, despite a prior history of chickenpox in two and pretransplant varicella vaccination in one (33). The clinical disease was mild and responded promptly to oral aciclovir. Although this was based on very few patients, the incidence of 16% was thought to be unexpectedly higher than that reported in historic controls (0.7-1.9%), and might have resulted from the higher degree of immunosuppression achieved with mycophenolate mofetil. 

To evalnate whether mycophenolate mofetil is effective in treating moderate to severe atopic dermatitis, an open pilot stndy was condncted in 10 patients (34). There were no serions adverse effects, bnt one patient had to discon-tinne treatment becanse he developed Herpes simplex retinitis, which resolved after treatment with aciclovir. Althongh there is no direct evidence that mycophenolate mofetil is a major canse of Herpes retinitis, in this patient it seems likely that it was dne to immunosuppression. In contrast, in vivo and in vitro mycophenolate mofetil strongly potentiates the antiherpetic effects of aciclovir, ganciclovir, and penciclovir (35). It is probably therefore enough to give antiviral therapy only when clinical signs of Herpes infection occur. 

The concurrent use of aciclovir or ganciclovir and mycophenolate mofetil does not appear to significantly affect the pharmacokinetics of either drug, but the manufacturers recommend care in renal impairment. There are reports of neutropenia in patients taking mycophenolate with valaciclovir or ganciclovir. 

Gimenez F, Foeillet E, Bourdon O, Weller S, Garret C, Bidault R, Singlas E. Evaluation of pharmacokinetic interactions after oral administration of mycophenolate mofetil and valaciclovir or aciclovir to healftiy subjects. Clin Pharmacokinet (2004) 43, 685-92. 

Mycophenolate mofetil An interaction of aciclovir with mycophenolate mofetil has been reported [20 ]. 

The authors proposed that mycophenolate mofetil may have enhanced the neurotoxicity of aciclovir, since mycophenolate is thought not to be neurotoxic. Mycophenolic acid is metabolized in the liver to mycophenolic glu-curonide, which may compete with aciclovir for renal tubular secretion. As the combination of mycophenolate mofetil with aciclovir has been reported to have a possible synergistic antiherpes effect, it is important to be aware of a possible increase in the risk of neurotoxicity associated with this combination. 

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