FDA label e35e2d25-ec31-4176-88ea-e5e70a1047da

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warnings and cautions

5 WARNINGS AND PRECAUTIONS Acute renal failure: Cases of acute renal failure have been reported in patients with underlying renal disease who have received inappropriately high doses of famciclovir for their level of renal function. Dosage reduction is recommended when administering famciclovir to patients with renal impairment [see Dosage and Administration (2.3) , Use in Specific Populations (8.6) ] . Acute renal failure: May occur in patients with underlying renal disease who receive higher than recommended doses of famciclovir for their level of renal function. Reduce dosage in patients with renal impairment. (2.3 , 8.6)

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adverse reactions

6 ADVERSE REACTIONS Acute renal failure is discussed in greater detail in other sections of the label [see Warnings and Precautions (5) ] . The most common adverse events reported in at least 1 indication by >10% of adult patients treated with famciclovir are headache and nausea. The most common adverse events reported in at least 1 indication by >10% of adult patients are headache and nausea. (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Northstar Rx LLC at 1-800-206-7821 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience in Adult Patients Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared with rates in the clinical trials of another drug and may not reflect the rates observed in practice. Immunocompetent patients: The safety of famciclovir has been evaluated in active- and placebo-controlled clinical studies involving 816 famciclovir-treated patients with herpes zoster (famciclovir, 250 mg three times daily to 750 mg three times daily); 163 famciclovir-treated patients with recurrent genital herpes (famciclovir, 1000 mg twice daily); 1,197 patients with recurrent genital herpes treated with famciclovir as suppressive therapy (125 mg once daily to 250 mg three times daily) of which 570 patients received famciclovir (open-labeled and/or double-blind) for at least 10 months; and 447 famciclovir-treated patients with herpes labialis (famciclovir, 1500 mg once daily or 750 mg twice daily). Table 2 lists selected adverse events. Table 2 Selected Adverse Events (all grades and without regard to causality) Reported by ≥ 2% of Patients in Placebo-Controlled Famciclovir Trials* * Patients may have entered into more than one clinical trial. † 7 days of treatment ‡ 1 day of treatment § daily treatment Incidence Events Herpes Zoster † Recurrent Genital Herpes‡ Genital Herpes- Suppression§ Herpes Labialis‡ Famciclovir (n=273) % Placebo (n=146) % Famciclovir (n=163) % Placebo (n=166) % Famciclovir (n=458) % Placebo (n=63) % Famciclovir (n=447) % Placebo (n=254) % Nervous System Headache 22.7 17.8 13.5 5.4 39.3 42.9 8.5 6.7 Paresthesia 2.6 0 0 0 0.9 0 0 0 Migraine 0.7 0.7 0.6 0.6 3.1 0 0.2 0 Gastrointestinal Nausea 12.5 11.6 2.5 3.6 7.2 9.5 2.2 3.9 Diarrhea 7.7 4.8 4.9 1.2 9 9.5 1.6 0.8 Vomiting 4.8 3.4 1.2 0.6 3.1 1.6 0.7 0 Flatulence 1.5 0.7 0.6 0 4.8 1.6 0.2 0 Abdominal Pain 1.1 3.4 0 1.2 7.9 7.9 0.2 0.4 Body as a Whole Fatigue 4.4 3.4 0.6 0 4.8 3.2 1.6 0.4 Skin and Appendages Pruritus 3.7 2.7 0 0.6 2.2 0 0 0 Rash 0.4 0.7 0 0 3.3 1.6 0 0 Reproductive (Female) Dysmenorrhea 0 0.7 1.8 0.6 7.6 6.3 0.4 0 Table 3 lists selected laboratory abnormalities in genital herpes suppression trials. Table 3 Selected Laboratory Abnormalities in Genital Herpes Suppression Studies* * Percentage of patients with laboratory abnormalities that were increased or decreased from baseline and were outside of specified ranges. † n values represent the minimum number of patients assessed for each laboratory parameter. NRH = Normal Range High. NRL = Normal Range Low. Parameter Famciclovir (n = 660) † % Placebo (n = 210) † % Anemia (<0.8 x NRL) 0.1 0 Leukopenia (<0.75 x NRL) 1.3 0.9 Neutropenia (<0.8 x NRL) 3.2 1.5 AST (SGOT) (>2 x NRH) 2.3 1.2 ALT (SGPT) (>2 x NRH) 3.2 1.5 Total Bilirubin (>1.5 x NRH) 1.9 1.2 Serum Creatinine (>1.5 x NRH) 0.2 0.3 Amylase (>1.5 x NRH) 1.5 1.9 Lipase (>1.5 x NRH) 4.9 4.7 HIV-infected patients: In HIV-infected patients, the most frequently reported adverse events for famciclovir (500 mg twice daily; n=150) and acyclovir (400 mg, 5x/day; n=143), respectively, were headache (17% vs. 15%), nausea (11% vs. 13%), diarrhea (7% vs. 11%), vomiting (5% vs. 4%), fatigue (4% vs. 2%), and abdominal pain (3% vs. 6%). 6.2 Postmarketing Experience The adverse events listed below have been reported during postapproval use of famciclovir. Because these events are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure: Blood and lymphatic system disorders: Thrombocytopenia Hepatobiliary disorders: Abnormal liver function tests, cholestatic jaundice Immune system disorders: Anaphylactic shock, anaphylactic reaction Nervous system disorders: Dizziness, somnolence, seizure Psychiatric disorders: Confusion (including delirium, disorientation, and confusional state occurring predominantly in the elderly), hallucinations Skin and subcutaneous tissue disorders: Urticaria, erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis, angioedema (e.g., face, eyelid, periorbital, and pharyngeal edema), hypersensitivity vasculitis Cardiac disorders: Palpitations

adverse reactions table

<table border="0" cellpadding="0" cellspacing="0" width="100%"> <caption>Table 2 Selected Adverse Events (all grades and without regard to causality) Reported by &#x2265; 2% of Patients in Placebo-Controlled Famciclovir Trials*</caption> <tfoot> <tr> <td colspan="179"> <sup>*</sup> Patients may have entered into more than one clinical trial. <sup>&#x2020;</sup>7 days of treatment <sup>&#x2021;</sup> 1 day of treatment <sup>&#xA7;</sup> daily treatment </td> </tr> </tfoot> <tbody> <tr styleCode="Botrule"> <td align="center" colspan="9" styleCode="Lrule Rrule" valign="top"> <content styleCode="bold">Incidence</content> <content styleCode="bold"/> </td> </tr> <tr styleCode="Botrule"> <td align="center" rowspan="2" styleCode="Lrule Rrule" valign="top"> <content styleCode="bold">Events</content> </td> <td align="center" colspan="2" styleCode="Rrule" valign="top"> <content styleCode="bold">Herpes Zoster</content> <content styleCode="bold"> <sup>&#x2020;</sup> </content> </td> <td align="center" colspan="2" styleCode="Rrule" valign="top"> <content styleCode="bold">Recurrent Genital</content> <content styleCode="bold">Herpes&#x2021;</content> </td> <td align="center" colspan="2" styleCode="Rrule" valign="top"> <content styleCode="bold">Genital Herpes-</content> <content styleCode="bold">Suppression&#xA7;</content> </td> <td align="center" colspan="2" styleCode="Rrule" valign="top"> <content styleCode="bold">Herpes Labialis&#x2021;</content> </td> </tr> <tr styleCode="Botrule"> <td align="center" styleCode="Lrule Rrule" valign="top"> <content styleCode="bold">Famciclovir</content> <content styleCode="bold">(n=273) </content> <content styleCode="bold">% </content> </td> <td align="center" styleCode="Rrule" valign="top"> <content styleCode="bold">Placebo</content> <content styleCode="bold">(n=146) % </content> </td> <td align="center" styleCode="Rrule" valign="top"> <content styleCode="bold">Famciclovir</content> <content styleCode="bold">(n=163)</content> <content styleCode="bold">% </content> </td> <td align="center" styleCode="Rrule" valign="top"> <content styleCode="bold">Placebo</content> <content styleCode="bold">(n=166)</content> <content styleCode="bold">% </content> </td> <td align="center" styleCode="Rrule" valign="top"> <content styleCode="bold">Famciclovir</content> <content styleCode="bold">(n=458) </content> <content styleCode="bold">% </content> </td> <td align="center" styleCode="Rrule" valign="top"> <content styleCode="bold">Placebo</content> <content styleCode="bold">(n=63)</content> <content styleCode="bold">% </content> </td> <td align="center" styleCode="Rrule" valign="top"> <content styleCode="bold">Famciclovir</content> <content styleCode="bold">(n=447)</content> <content styleCode="bold">% </content> </td> <td align="center" styleCode="Rrule" valign="top"> <content styleCode="bold">Placebo</content> <content styleCode="bold">(n=254)</content> <content styleCode="bold">% </content> </td> </tr> <tr styleCode="Botrule"> <td colspan="9" styleCode="Lrule Rrule" valign="top"> <content styleCode="bold"> Nervous System</content> <content styleCode="bold"/> </td> </tr> <tr styleCode="Botrule"> <td align="center" styleCode="Lrule Rrule" valign="top">Headache<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">22.7<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">17.8<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">13.5 </td> <td align="center" styleCode="Rrule" valign="top">5.4 </td> <td align="center" styleCode="Rrule" valign="top">39.3 </td> <td align="center" styleCode="Rrule" valign="top">42.9 </td> <td align="center" styleCode="Rrule" valign="top">8.5 </td> <td align="center" styleCode="Rrule" valign="top">6.7 </td> </tr> <tr styleCode="Botrule"> <td align="center" styleCode="Lrule Rrule" valign="top">Paresthesia<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">2.6<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">0<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">0 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> <td align="center" styleCode="Rrule" valign="top">0.9 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> </tr> <tr styleCode="Botrule"> <td align="center" styleCode="Lrule Rrule" valign="top">Migraine<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">0.7<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">0.7<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">0.6 </td> <td align="center" styleCode="Rrule" valign="top">0.6 </td> <td align="center" styleCode="Rrule" valign="top">3.1 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> <td align="center" styleCode="Rrule" valign="top">0.2 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> </tr> <tr styleCode="Botrule"> <td colspan="9" styleCode="Lrule Rrule" valign="top"> <content styleCode="bold"> Gastrointestinal</content> <content styleCode="bold"/> </td> </tr> <tr styleCode="Botrule"> <td align="center" styleCode="Lrule Rrule" valign="top">Nausea<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">12.5<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">11.6<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">2.5 </td> <td align="center" styleCode="Rrule" valign="top">3.6 </td> <td align="center" styleCode="Rrule" valign="top">7.2 </td> <td align="center" styleCode="Rrule" valign="top">9.5 </td> <td align="center" styleCode="Rrule" valign="top">2.2 </td> <td align="center" styleCode="Rrule" valign="top">3.9 </td> </tr> <tr styleCode="Botrule"> <td align="center" styleCode="Lrule Rrule" valign="top">Diarrhea<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">7.7<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">4.8<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">4.9 </td> <td align="center" styleCode="Rrule" valign="top">1.2 </td> <td align="center" styleCode="Rrule" valign="top">9 </td> <td align="center" styleCode="Rrule" valign="top">9.5 </td> <td align="center" styleCode="Rrule" valign="top">1.6 </td> <td align="center" styleCode="Rrule" valign="top">0.8 </td> </tr> <tr styleCode="Botrule"> <td align="center" styleCode="Lrule Rrule" valign="top">Vomiting<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">4.8<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">3.4<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">1.2 </td> <td align="center" styleCode="Rrule" valign="top">0.6 </td> <td align="center" styleCode="Rrule" valign="top">3.1 </td> <td align="center" styleCode="Rrule" valign="top">1.6 </td> <td align="center" styleCode="Rrule" valign="top">0.7 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> </tr> <tr styleCode="Botrule"> <td align="center" styleCode="Lrule Rrule" valign="top">Flatulence<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">1.5<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">0.7<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">0.6 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> <td align="center" styleCode="Rrule" valign="top">4.8 </td> <td align="center" styleCode="Rrule" valign="top">1.6 </td> <td align="center" styleCode="Rrule" valign="top">0.2 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> </tr> <tr styleCode="Botrule"> <td align="center" styleCode="Lrule Rrule" valign="top">Abdominal Pain<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">1.1<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">3.4<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">0 </td> <td align="center" styleCode="Rrule" valign="top">1.2 </td> <td align="center" styleCode="Rrule" valign="top">7.9 </td> <td align="center" styleCode="Rrule" valign="top">7.9 </td> <td align="center" styleCode="Rrule" valign="top">0.2 </td> <td align="center" styleCode="Rrule" valign="top">0.4 </td> </tr> <tr styleCode="Botrule"> <td colspan="9" styleCode="Lrule Rrule" valign="top"> <content styleCode="bold"> Body as a Whole</content> <content styleCode="bold"/> </td> </tr> <tr styleCode="Botrule"> <td align="center" styleCode="Lrule Rrule" valign="top">Fatigue<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">4.4<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">3.4<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">0.6 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> <td align="center" styleCode="Rrule" valign="top">4.8 </td> <td align="center" styleCode="Rrule" valign="top">3.2 </td> <td align="center" styleCode="Rrule" valign="top">1.6 </td> <td align="center" styleCode="Rrule" valign="top">0.4 </td> </tr> <tr styleCode="Botrule"> <td colspan="9" styleCode="Lrule Rrule" valign="top"> <content styleCode="bold"> Skin and Appendages</content> <content styleCode="bold"/> </td> </tr> <tr styleCode="Botrule"> <td align="center" styleCode="Lrule Rrule" valign="top">Pruritus<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">3.7<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">2.7<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">0 </td> <td align="center" styleCode="Rrule" valign="top">0.6 </td> <td align="center" styleCode="Rrule" valign="top">2.2 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> </tr> <tr styleCode="Botrule"> <td align="center" styleCode="Lrule Rrule" valign="top">Rash<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">0.4<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">0.7<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">0 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> <td align="center" styleCode="Rrule" valign="top">3.3 </td> <td align="center" styleCode="Rrule" valign="top">1.6 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> </tr> <tr styleCode="Botrule"> <td colspan="9" styleCode="Lrule Rrule" valign="top"> <content styleCode="bold"> Reproductive (Female)</content> <content styleCode="bold"/> </td> </tr> <tr> <td align="center" styleCode="Lrule Rrule" valign="top">Dysmenorrhea<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">0<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">0.7<content styleCode="bold"/> </td> <td align="center" styleCode="Rrule" valign="top">1.8 </td> <td align="center" styleCode="Rrule" valign="top">0.6 </td> <td align="center" styleCode="Rrule" valign="top">7.6 </td> <td align="center" styleCode="Rrule" valign="top">6.3 </td> <td align="center" styleCode="Rrule" valign="top">0.4 </td> <td align="center" styleCode="Rrule" valign="top">0 </td> </tr> </tbody> </table>

adverse reactions table

<table border="0" cellpadding="0" cellspacing="0" width="100%"> <caption>Table 3 Selected Laboratory Abnormalities in Genital Herpes Suppression Studies* </caption> <tfoot> <tr> <td align="justify" colspan="3">* Percentage of patients with laboratory abnormalities that were increased or decreased from baseline and were outside of specified ranges. <sup>&#x2020;</sup> n values represent the minimum number of patients assessed for each laboratory parameter. NRH = Normal Range High. NRL = Normal Range Low. </td> </tr> </tfoot> <tbody> <tr styleCode="Botrule"> <td styleCode="Lrule Rrule" valign="top"> <content styleCode="bold"> Parameter </content> </td> <td align="center" styleCode="Rrule" valign="top"> <content styleCode="bold">Famciclovir</content> <content styleCode="bold"/> <content styleCode="bold">(n = 660)<sup>&#x2020;</sup> </content> <content styleCode="bold">%</content> </td> <td align="center" styleCode="Rrule" valign="top"> <content styleCode="bold">Placebo</content> <content styleCode="bold">(n = 210)<sup>&#x2020;</sup> </content> <content styleCode="bold">%</content> </td> </tr> <tr styleCode="Botrule"> <td styleCode="Lrule Rrule" valign="top"> Anemia (&lt;0.8 x NRL) </td> <td align="center" styleCode="Rrule" valign="top">0.1 </td> <td align="center" styleCode="Rrule" valign="top">0<content styleCode="bold"/> </td> </tr> <tr styleCode="Botrule"> <td styleCode="Lrule Rrule" valign="top"> Leukopenia (&lt;0.75 x NRL) </td> <td align="center" styleCode="Rrule" valign="top">1.3 </td> <td align="center" styleCode="Rrule" valign="top">0.9<content styleCode="bold"/> </td> </tr> <tr styleCode="Botrule"> <td styleCode="Lrule Rrule" valign="top"> Neutropenia (&lt;0.8 x NRL) </td> <td align="center" styleCode="Rrule" valign="top">3.2 </td> <td align="center" styleCode="Rrule" valign="top">1.5<content styleCode="bold"/> </td> </tr> <tr styleCode="Botrule"> <td styleCode="Lrule Rrule" valign="top"> AST (SGOT) (&gt;2 x NRH) </td> <td align="center" styleCode="Rrule" valign="top">2.3 </td> <td align="center" styleCode="Rrule" valign="top">1.2<content styleCode="bold"/> </td> </tr> <tr styleCode="Botrule"> <td styleCode="Lrule Rrule" valign="top"> ALT (SGPT) (&gt;2 x NRH) </td> <td align="center" styleCode="Rrule" valign="top">3.2 </td> <td align="center" styleCode="Rrule" valign="top">1.5<content styleCode="bold"/> </td> </tr> <tr styleCode="Botrule"> <td styleCode="Lrule Rrule" valign="top"> Total Bilirubin (&gt;1.5 x NRH) </td> <td align="center" styleCode="Rrule" valign="top">1.9 </td> <td align="center" styleCode="Rrule" valign="top">1.2<content styleCode="bold"/> </td> </tr> <tr styleCode="Botrule"> <td styleCode="Lrule Rrule" valign="top"> Serum Creatinine (&gt;1.5 x NRH) </td> <td align="center" styleCode="Rrule" valign="top">0.2 </td> <td align="center" styleCode="Rrule" valign="top">0.3<content styleCode="bold"/> </td> </tr> <tr styleCode="Botrule"> <td styleCode="Lrule Rrule" valign="top"> Amylase (&gt;1.5 x NRH) </td> <td align="center" styleCode="Rrule" valign="top">1.5 </td> <td align="center" styleCode="Rrule" valign="top">1.9<content styleCode="bold"/> </td> </tr> <tr> <td styleCode="Lrule Rrule" valign="top"> Lipase (&gt;1.5 x NRH) </td> <td align="center" styleCode="Rrule" valign="top">4.9 </td> <td align="center" styleCode="Rrule" valign="top">4.7<content styleCode="bold"/> </td> </tr> </tbody> </table>