Famciclovir 500 mg Tablet, Film Coated, 21-count
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🆔 Identity & classification
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🏷️ RxNorm drug class
This medicine belongs to the Herpes Simplex Virus Nucleoside Analog DNA Polymerase Inhibitor class.
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🏭 Manufacturer & labeler
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🩺 Clinical
- Famciclovir is an antiviral medication used to treat herpes virus infections in adults. It can treat cold sores, recurring genital herpes outbreaks, and shingles. If you get genita...
- Yes, timing really matters. For cold sores and genital herpes, famciclovir works best when you start it at the very first hint of an outbreak — that tingling, itching, or burning f...
- When should I take it — do I need to start right away when I feel an outbreak coming on?
- You can take famciclovir with or without food — it doesn't matter. Food can slow down how quickly the drug kicks in, but it doesn't reduce how much of it your body absorbs overall....
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🧪 Inactive Ingredients / Excipients
Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.
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💲 Pricing
A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.
| Price system | Per each | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | Not in the retail survey — common for institutional, discontinued, or low-volume packs. | |
| Medicaid paysCMS SDUD · 12 mo | No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data. | |
| Medicare drug plans payPart D · Q2 2026 | $0.4471 | $9.39 / 21 tablets |
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🔁 Therapeutic equivalents
| Product | Labeler | Pack | NADAC/unit | TE | Status | Price vs. this |
|---|---|---|---|---|---|---|
| Famciclovir 500 mg 00093-8119-56 | Teva | 30 tablets | $0.791 | — | Availability likely | — |
| Famciclovir 500 mg 33342-0026-07 | Macleods | 30 tablets | $0.791 | AB | Availability likely | — |
| Famciclovir 500 mg 60505-3247-03 | Apotex | 30 tablets | $0.791 | — | Discontinued | — |
| Famciclovir 500 mg 64980-0351-03 | Rising | 30 tablets | $0.791 | AB | Availability likely | — |
| Famciclovir 500 mg 31722-0708-01 | Camber | 100 tablets | — | AB | FDA listed | — |
| Famciclovir 500 mg 42291-0416-30 | AvKARE | 30 tablets | — | AB | FDA listed | — |
| Famciclovir 500 mg 55289-0168-03 | PD-Rx | 3 tablets | — | AB | FDA listed | — |
| Famciclovir 500 mg 63187-0998-21 | Proficient | 21 tablets | — | AB | FDA listed | — |
| Famciclovir 500 mg 63629-7890-01 | Bryant | 30 tablets | — | AB | FDA listed | — |
| Famciclovir 500 mg 65862-0467-05 | Aurobindo | 500 tablets | — | AB | FDA listed | — |
| Famciclovir 500 mgthis 71205-0609-21 | Proficient | 21 tablets | — | AB | FDA listed | — |
| Famciclovir 500 mg 71335-2936-01 | Bryant | 30 tablets | — | AB | FDA listed | — |
| Famciclovir 500 mg 73190-0093-30 | AvKARE | 30 tablets | — | AB | FDA listed | — |
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⏳ Availability & generic status
This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.
Where does this data come from?
📊 Medicare Part D spend CMS · PART D · 2026 (Q1)
🔬 Reported adverse events (FAERS)
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📦 Packaging — all sizes for this product
| Package NDC | Description | Marketing start | Status |
|---|---|---|---|
| 71205-0609-21 You're viewing this | 21 TABLET, FILM COATED in 1 BOTTLE (71205-609-21) | 2021-10-04 | Active |
| 71205-0609-30 | 30 TABLET, FILM COATED in 1 BOTTLE (71205-609-30) | 2021-10-04 | Active |
| 71205-0609-60 | 60 TABLET, FILM COATED in 1 BOTTLE (71205-609-60) | 2021-10-04 | Active |
| 71205-0609-90 | 90 TABLET, FILM COATED in 1 BOTTLE (71205-609-90) | 2021-10-04 | Active |
You're viewing the smallest of 4 pack sizes for this product.
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What quantity is in NDC 71205-0609-21?
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🧭 About this NDC listing & data coverage
What data is (and isn’t) available for this NDC — tap to expand
| NDC identity (package / product / labeler codes) | ✓ Available |
| Labeler | ✓ Available |
| Product & package description | ✓ Available |
| Marketing category & status | ✓ Available |
| Active ingredient / dosage form / route | ✓ Available |
| FDA label (SPL via DailyMed) | ✓ Available |
| Package photos | — Not published for this NDC No photo available yet for this listing. |
| Inactive ingredients (structured) | — Not published for this NDC The labeler did not submit a structured excipient list, or no SPL is available. |
| NADAC pharmacy acquisition price (CMS) | — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey. |
| Orange Book / therapeutic-equivalence data | ✓ Available |
| HCPCS J-code billing crosswalk | — Not published for this NDC Most self-administered / retail products have no J-code — that is normal. |
| Medicaid utilization (CMS SDUD) | — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold. |
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📄 Full prescribing information FDA SPL
🎯 Indications and Usage ▾
1 INDICATIONS & USAGE Famciclovir, USP a prodrug of penciclovir, is a deoxynucleoside analogue DNA polymerase inhibitor indicated for: Immunocompetent Adult Patients ( 1.1 ) • Herpes labialis (cold sores) o Treatment of recurrent episodes • Genital herpes o Treatment of recurrent episodes o Suppressive therapy of recurrent episodes • Herpes zoster (shingles) Human Immunodeficiency Virus (HIV) -Infected Adult Patients ( 1.2 ) • Treatment of recurrent episodes of orolabial or genital herpes Limitation of Use The efficacy and safety of famciclovir have not been established for: • Patients with first episode of genital herpes • Patients with ophthalmic zoster • Immunocompromised patients other than for the treatment of recurrent episodes of orolabial or genital herpes in HIV- infected patients • Black and African American patients with recurrent genital herpes
1.1Immunocompetent Adult Patient Herpes labialis(cold sores): Famciclovir is indicated for the treatment of recurrent herpes labialis in adult patients. Genital herpes: Recurrent episodes: Famciclovir is indicated for the treatment of recurrent episodes of genital herpes. The efficacy of famciclovir when initiated more than 6 hours after onset of symptoms or lesions has not been established.
Suppressive therapy: Famciclovir is indicated for chronic suppressive therapy of recurrent episodes of genital herpes in adult patients. The efficacy and safety of famciclovir for the suppression of recurrent genital herpes beyond 1 year have not been established. Herpes zoster (shingles): Famciclovir is indicated for the treatment of herpes zoster in adult patients.
The efficacy of famciclovir when initiated more than 72 hours after onset of rash has not been established.
1.2HIV-Infected Adult Patients Recurrent orolabial or genital herpes: Famciclovir, USP is indicated for the treatment of recurrent episodes of orolabial or genital herpes in HIV-infected adults. The efficacy of famciclovir, USP when initiated more than 48 hours after onset of symptoms or lesions has not been established. Limitation of Use The efficacy and safety of famciclovir have not been established for: • Patients with first episode of genital herpes • Patients with ophthalmic zoster • Immunocompromised patients other than for the treatment of recurrent orolabial or genital herpes in HIV-infected patients • Black and African American patients with recurrent genital herpes
⏱️ Dosage and Administration ▾
2 DOSAGE & ADMINISTRATION Famciclovir Tablets may be taken with or without food. Immunocompetent Adult Patients ( 2.1 ) Herpes labialis (cold sores) 1500 mg as a single dose Genital herpes Treatment of recurrent episodes 1000 mg twice daily for 1 day Suppressive therapy 250 mg twice daily Herpes zoster (shingles) 500 mg every 8 hours for 7 days HIV-Infected Adult Patients ( 2.1 ) Recurrent episodes of orolabial or genital herpes 500 mg twice daily for 7 days Patients with renal impairment: Adjust dose based on creatinine clearance.
( 2.3 )
2.1Dosing Recommendation in Immunocompetent Adult Patients Herpes labialis (cold sores): The recommended dosage of famciclovir for the treatment of recurrent herpes labialis is 1500 mg as a single dose. Therapy should be initiated at the first sign or symptom of herpes labialis (e.g., tingling, itching, burning, pain, or lesion). Genital herpes: Recurrent episodes : The recommended dosage of famciclovir for the treatment of recurrent episodes of genital herpes is 1000 mg twice daily for 1 day.
Therapy should be initiated at the first sign or symptom of a recurrent episode (e.g., tingling, itching, burning, pain, or lesion). Suppressive therapy: The recommended dosage of famciclovir for chronic suppressive therapy of recurrent episodes of genital herpes is 250 mg twice daily. Herpes zoster (shingles): The recommended dosage of famciclovir for the treatment of herpes zoster is 500 mg every 8 hours for 7 days.
Therapy should be initiated as soon as herpes zoster is diagnosed.
2.2Dosing Recommendation in HIV-Infected Adult Patients Recurrent orolabial or genital herpes: The recommended dosage of famciclovir for the treatment of recurrent orolabial or genital herpes in HIV-infected patients is 500 mg twice daily for 7 days. Therapy should be initiated at the first sign or symptom of a recurrent episode (e.g., tingling, itching, burning, pain, or lesion).
2.3Dosing Recommendation in Patients with Renal Impairment Dosage recommendations for adult patients with renal impairment are provided in Table 1 [see Use in Specific Populations ( 8.6 ), Clinical Pharmacology ( 12.3 )]. Table 1: Dosage Recommendations for Adult Patients Indication and Normal Dosage Regimen Creatinine Clearance (mL/min.) Adjusted Dosage Regimen Dose (mg) Dosing Interval Single-Day Dosing Regimens Recurrent Genital Herpes 1000 mg every 12 hours for 1 day ≥60 1000 every 12 hours for 1 day 40 to 59 500 every 12 hours for 1 day 20 to 39 500 single dose <20 250 single dose HD* 250 single dose following dialysis Recurrent Herpes Labialis 1500 mg single dose ≥60 1500 single dose 40 to 59 750 single dose 20 to 39 500 single dose <20 250 single dose HD* 250 single dose following dialysis Multiple-Day Dosing Regimens Herpes Zoster 500 mg every 8 hours ≥60 500 every 8 hours 40 to 59 500 every 12 hours 20 to 39 500 every 24 hours <20 250 every 24 hours HD* 250 following each dialysis Suppression of Recurrent Genital Herpes 250 mg every 12 hours ≥40 250 every 12 hours 20 to 39 125 every 12 hours <20 125 every 24 hours HD* 125 following each dialysis Recurrent Orolabial or Genital Herpes in HIV-Infected Patients 500 mg every 12 hours ≥40 500 every 12 hours 20 to 39 500 every 24 hours <20 250 every 24 hours HD* 250 following each dialysis * Hemodialysis
💊 Dosage Forms and Strengths ▾
3 DOSAGE FORMS & STRENGTHS Famciclovir tablets, USP are available in 3 strengths: •25 mg: White to off white, round film-coated, biconvex, engraved with "ML 67" on one side and plain on the other side. •250 mg: White to off white, round film-coated, biconvex, engraved with "ML 70" on one side and plain on the other side. •500 mg: White to off white, oval film-coated, biconvex, engraved with "ML 72" on one side and plain on the other side. Tablets : 125mg, 250mg, 500mg ( 3 )
⛔ Contraindications ▾
4 CONTRAINDICATIONS Famciclovir tablets are contraindicated in patients with known hypersensitivity to the product, its components, or Denavir ® (penciclovir cream). Known hypersensitivity to the product, its components, or Denavir ® (penciclovir cream) ( 4 )
⚠️ Warnings and Cautions ▾
5 WARNINGS AND PRECAUTIONS 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 )
5.1Acute 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 tablets to patients with renal impairment [see Dosage and Administration ( 2.3 ), Use in Specific Populations ( 8.6 )].
🤒 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 greater than 10% of adult patients treated with famciclovir are headache and nausea. The most common adverse events reported in at least 1 indication by greater than 10% of adult patients are headache and nausea.
( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Macleods Pharma USA Inc. at 1-888-943-3210 or 1-855-926-3384 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch
6.1Clinical Trials Experience in Adult Patient 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 Greater Than or Equal to 2% of Patients in Placebo-Controlled famciclovir Trials Patients may have entered into more than one clinical trial Incidence Events Herpes Zoster 7 days of treatment Recurrent Genital Herpes 1 day of treatment Genital Herpes- Suppression daily treatment 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
6.7Paresthesia 2.6 0.0 0.0 0.0 0.9 0.0 0.0
0.0Migraine 0.7 0.7 0.6 0.6 3.1 0.0 0.2
0.0Gastrointestinal Nausea 12.5 11.6 2.5 3.6 7.2 9.5 2.2
3.9Diarrhea 7.7 4.8 4.9 1.2 9.0 9.5 1.6
0.8Vomiting 4.8 3.4 1.2 0.6 3.1 1.6 0.7
0.0Flatulence 1.5 0.7 0.6 0.0 4.8 1.6 0.2
0.0Abdominal Pain 1.1 3.4 0.0 1.2 7.9 7.9 0.2
0.4Body as a Whole Fatigue 4.4 3.4 0.6 0.0 4.8 3.2 1.6
0.4Skin and Appendages Pruritus 3.7 2.7 0.0 0.6 2.2 0.0 0.0
0.0Rash 0.4 0.7 0.0 0.0 3.3 1.6 0.0
0.0Reproductive Female Dysmenorrhea 0.0 0.7 1.8 0.6 7.6 6.3 0.4
0.0Table 3: 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. Parameter Famciclovir (n = 660) n values represent the minimum number of patients assessed for each laboratory parameter. % Placebo (n = 210) % Anemia (<0.8 x NRL) 0.1
0.0Leukopenia (<0.75 x NRL) 1.3
0.9Neutropenia (<0.8 x NRL) 3.2
1.5AST (SGOT) (>2 x NRH) 2.3
1.2ALT (SGPT) (>2 x NRH) 3.2
1.5Total Bilirubin (>1.5 x NRH) 1.9
1.2Serum Creatinine (>1.5 x NRH) 0.2
0.3Amylase (>1.5 x NRH) 1.5
1.9Lipase (>1.5 x NRH) 4.9
4.7NRH = Normal Range High. NRL = Normal Range Low. 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%).
6.2Postmarketing Experience The adverse events listed below have been reported during post-…
🔄 Drug Interactions ▾
7 DRUG INTERACTIONS Probenecid: May increase penciclovir levels. Monitor for evidence of penciclovir toxicity ( 7.2 )
7.1Potential for famciclovir to Affect Other Drugs The steady-state pharmacokinetics of digoxin were not altered by concomitant administration of multiple doses of famciclovir (500 mg three times daily). No clinically significant effect on the pharmacokinetics of zidovudine, its metabolite zidovudine glucuronide, or emtricitabine was observed following a single oral dose of 500 mg famciclovir coadministered with zidovudine or emtricitabine. An in vitro study using human liver microsomes suggests that famciclovir is not an inhibitor of CYP3A4 enzymes.
7.2Potential for Other Drugs to Affect Penciclovir No clinically significant alterations in penciclovir pharmacokinetics were observed following single-dose administration of 500 mg famciclovir after pretreatment with multiple doses of allopurinol, cimetidine, theophylline, zidovudine, promethazine, when given shortly after an antacid (magnesium and aluminum hydroxide), or concomitantly with emtricitabine. No clinically significant effect on penciclovir pharmacokinetics was observed following multiple-dose (three times daily) administration of famciclovir (500 mg) with multiple doses of digoxin.
Concurrent use with probenecid or other drugs significantly eliminated by active renal tubular secretion may result in increased plasma concentrations of penciclovir. The conversion of 6-deoxy penciclovir to penciclovir is catalyzed by aldehyde oxidase. Interactions with other drugs metabolized by this enzyme and/or inhibiting this enzyme could potentially occur.
Clinical interaction studies of famciclovir with cimetidine and promethazine, in vitro inhibitors of aldehyde oxidase, did not show relevant effects on the formation of penciclovir. Raloxifene, a potent aldehyde oxidase inhibitor in vitro, could decrease the formation of penciclovir. However, a clinical drug-drug interaction study to determine the magnitude of interaction between penciclovir and raloxifene has not been conducted.
👥 Use in Specific Populations ▾
8 USE IN SPECIFIC POPULATIONS
8.1Pregnancy Risk Summary Available data from pharmacovigilance reports with famciclovir use in pregnant women have not identified a drug-associated risk of major birth defects, miscarriage or adverse maternal or fetal outcomes. There are risks to the fetus associated with untreated herpes simplex virus during pregnancy ( see Clinical Considerations ). After oral administration, famciclovir (prodrug) is converted to penciclovir (active drug).
In animal reproduction studies with famciclovir, no evidence of adverse developmental outcomes was observed at systemic exposures of penciclovir (AUC) slightly higher than those at the maximum recommended human dose (MRHD) of famciclovir ( see Data ). The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes.
In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15- 20%, respectively. Clinical Considerations Disease-associated maternal and/or embryo-fetal risk The risk of neonatal herpes infection varies from 30% to 50% for genital herpes simplex virus (HSV) infections that occur in late pregnancy (third trimester), whereas in early pregnancy, infection carries a risk of about 1%. A primary herpes outbreak during the first trimester of pregnancy has been associated with neonatal chorioretinitis, microcephaly and, in rare cases, skin lesions.
In very rare cases, transplacental transmission can occur resulting in congenital infection, including microcephaly, hepatosplenomegaly, intrauterine growth restriction and stillbirth. Co-infection with HSV increases the risk of perinatal HIV transmission in women who had a clinical diagnosis of genital herpes during pregnancy. Data Animal Data Famciclovir was administered orally to pregnant rats and rabbits (up to 1000 mg/kg/day) on gestation Day(s) 6 to 15, and to rats on gestation Day 15 to lactation/post-partum Day 25.
No adverse effects on embryo-fetal (rats and rabbits) or pre/post-natal (rats) development were observed up to the highest dose tested. During organogenesis, systemic exposures of penciclovir (active metabolite) were 3.4 times (rats) and 1.6 times (rabbits) the human systemic exposure of penciclovir based on AUC at the MRHD.
8.2Lactation Risk Summary There are no data on the presence of famciclovir (prodrug) or penciclovir (active drug) in human milk, the effects on the breastfed infant, or the effects on milk production. Animal data indicate that penciclovir is present in the milk of lactating rats (see Data). The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for famciclovir and any potential adverse effects on the breastfed infant from famciclovir or from the underlying maternal condition.
Data Penciclovir was the primary drug-related component excreted into the milk of lactating rats following a single oral dose of 40 mg per kg on lactation Day 12, with milk concentrations of up to approximately 8 times that of maternal plasma concentrations observed 0.5 hours postdose.
8.3Females and males of Reproductive Potential Infertility Decreased fertility, due to testicular toxicity, was observed in male animals following repeated administration of famciclovir or penciclovir [ see Nonclinical Toxicology ( 13.1 )]. In two placebo-controlled studies, 130 men with a history of recurrent genital herpes received either oral famciclovir (250 mg twice daily; n=66) or placebo (n=64) therapy for 18 weeks. The men were otherwise healthy and had a normal sperm profile prior to treatment.
There was no evidence of significant effects on sperm count, motility or morphology during famciclovir treatment or during an 8-week follow-up.
8.4Pediatric Use The efficacy of famciclovir tablets has not been established in pediatric pa…
🤰 Pregnancy ▾
8.1Pregnancy Risk Summary Available data from pharmacovigilance reports with famciclovir use in pregnant women have not identified a drug-associated risk of major birth defects, miscarriage or adverse maternal or fetal outcomes. There are risks to the fetus associated with untreated herpes simplex virus during pregnancy ( see Clinical Considerations ). After oral administration, famciclovir (prodrug) is converted to penciclovir (active drug).
In animal reproduction studies with famciclovir, no evidence of adverse developmental outcomes was observed at systemic exposures of penciclovir (AUC) slightly higher than those at the maximum recommended human dose (MRHD) of famciclovir ( see Data ). The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes.
In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15- 20%, respectively. Clinical Considerations Disease-associated maternal and/or embryo-fetal risk The risk of neonatal herpes infection varies from 30% to 50% for genital herpes simplex virus (HSV) infections that occur in late pregnancy (third trimester), whereas in early pregnancy, infection carries a risk of about 1%. A primary herpes outbreak during the first trimester of pregnancy has been associated with neonatal chorioretinitis, microcephaly and, in rare cases, skin lesions.
In very rare cases, transplacental transmission can occur resulting in congenital infection, including microcephaly, hepatosplenomegaly, intrauterine growth restriction and stillbirth. Co-infection with HSV increases the risk of perinatal HIV transmission in women who had a clinical diagnosis of genital herpes during pregnancy. Data Animal Data Famciclovir was administered orally to pregnant rats and rabbits (up to 1000 mg/kg/day) on gestation Day(s) 6 to 15, and to rats on gestation Day 15 to lactation/post-partum Day 25.
No adverse effects on embryo-fetal (rats and rabbits) or pre/post-natal (rats) development were observed up to the highest dose tested. During organogenesis, systemic exposures of penciclovir (active metabolite) were 3.4 times (rats) and 1.6 times (rabbits) the human systemic exposure of penciclovir based on AUC at the MRHD.
🧒 Pediatric Use ▾
8.4Pediatric Use The efficacy of famciclovir tablets has not been established in pediatric patients. The pharmacokinetic profile and safety of famciclovir (experimental granules mixed with OraSweet ® or tablets) were studied in 2 open-label studies. Study 1 was a single-dose pharmacokinetic and safety study in infants 1 month to less than 1 year of age who had an active herpes simplex virus (HSV) infection or who were at risk for HSV infection.
Eighteen subjects were enrolled and received a single dose of famciclovir experimental granules mixed with OraSweet based on the patient’s body weight (doses ranged from 25 mg to 175 mg). These doses were selected to provide penciclovir systemic exposures similar to the penciclovir systemic exposures observed in adults after administration of 500 mg famciclovir. The efficacy and safety of famciclovir have not been established as suppressive therapy in infants following neonatal HSV infections.
In addition, the efficacy cannot be extrapolated from adults to infants because there is no similar disease in adults. Therefore, famciclovir is not recommended in infants. Study 2 was an open-label, single-dose pharmacokinetic, multiple-dose safety study of famciclovir experimental granules mixed with OraSweet in children 1 to less than 12 years of age with clinically suspected HSV or varicella zoster virus (VZV) infection.
Fifty-one subjects were enrolled in the pharmacokinetic part of the study and received a single body weight adjusted dose of famciclovir (doses ranged from 125 mg to 500 mg). These doses were selected to provide penciclovir systemic exposures similar to the penciclovir systemic exposures observed in adults after administration of 500 mg famciclovir. Based on the pharmacokinetic data observed with these doses in children, a new weight-based dosing algorithm was designed and used in the multiple-dose safety part of the study.
Pharmacokinetic data were not obtained with the revised weight-based dosing algorithm. A total of 100 patients were enrolled in the multiple-dose safety part of the study; 47 subjects with active or latent HSV infection and 53 subjects with chickenpox. Patients with active or latent HSV infection received famciclovir twice a day for 7 days.
The daily dose of famciclovir ranged from 150 mg to 500 mg twice daily depending on the patient’s body weight. Patients with chickenpox received famciclovir three times daily for 7 days. The daily dose of famciclovir ranged from 150 mg to 500 mg three times daily depending on the patient’s body weight.
The clinical adverse events and laboratory test abnormalities observed in this study were similar to these seen in adults. The available data are insufficient to support the use of famciclovir for the treatment of children 1 to less than 12 years of age with chickenpox or infections due to HSV for the following reasons: Chickenpox: The efficacy of famciclovir for the treatment of chickenpox has not been established in either pediatric or adult patients. Famciclovir is approved for the treatment of herpes zoster in adult patients.
However, extrapolation of efficacy data from adults with herpes zoster to children with chickenpox would not be appropriate. Although chickenpox and herpes zoster are caused by the same virus, the diseases are different. Genital herpes: Clinical information on genital herpes in children is limited.
Therefore, efficacy data from adults cannot be extrapolated to this population. Further, famciclovir has not been studied in children 1 to less than 12 years of age with recurrent genital herpes. None of the children in Study 2 had genital herpes.
Herpes labialis: There are no pharmacokinetic and safety data in children 1 to <12 years of age to support a famciclovir dose that provides penciclovir systemic exposures comparable to the penciclovir systemic exposures in adults after a single dose administration of 1500 mg. Moreover, no efficacy data have been obtained in children 1 to less than 12 years of…
🧓 Geriatric Use ▾
8.5Geriatric Use Of 816 patients with herpes zoster in clinical studies who were treated with famciclovir, 248 (30.4%) were greater than or equal to 65 years of age and 103 (13%) were greater than or equal to 75 years of age. No overall differences were observed in the incidence or types of adverse events between younger and older patients. Of 610 patients with recurrent herpes simplex (type 1 or type 2) in clinical studies who were treated with famciclovir, 26 (4.3%) were greater than 65 years of age and 7 (1.1%) were greater than 75 years of age.
Clinical studies of famciclovir in patients with recurrent genital herpes did not include sufficient numbers of subjects aged 65 years and over to determine whether they respond differently compared to younger subjects. No famciclovir dosage adjustment based on age is recommended unless renal function is impaired [see Dosage and Administration ( 2.3 ), Clinical Pharmacology ( 12.3 )]. In general, appropriate caution should be exercised in the administration and monitoring of famciclovir in elderly patients reflecting the greater frequency of decreased renal function and concomitant use of other drugs.
🆘 Overdosage ▾
10 OVERDOSAGE Appropriate symptomatic and supportive therapy should be given. Penciclovir is removed by hemodialysis
🧬 Clinical Pharmacology ▾
12 CLINICAL PHARMACOLOGY
12.1Mechanism of Action Famciclovir is an orally administered prodrug of the anti-alpha herpes viral agent penciclovir [ see Microbiology ( 12.4 )].
12.3Pharmacokinetics Famciclovir is the diacetyl 6-deoxy analog of the active antiviral compound penciclovir. Following oral administration famciclovir undergoes rapid and extensive metabolism to penciclovir and little or no famciclovir is detected in plasma or urine. Penciclovir is predominantly eliminated unchanged by the kidney.
Therefore, the dose of famciclovir needs to be adjusted in patients with different degrees of renal impairment [see Dosage and Administration ( 2.3 )]. Pharmacokinetics in adults: Absorption and Bioavailability: The absolute bioavailability of penciclovir is 77 ± 8% as determined following the administration of a 500 mg famciclovir oral dose and a 400 mg penciclovir intravenous dose to 12 healthy male subjects. Penciclovir concentrations increased in proportion to dose over a famciclovir dose range of 125 mg to 1000 mg administered as a single dose.
Table 5 shows the mean pharmacokinetic parameters of penciclovir after single administration of famciclovir to healthy male volunteers. Table 1: Mean Pharmacokinetic Parameters of Penciclovir in Healthy Adult Subjects Based on pharmacokinetic data from 17 studies Dose AUC (0-inf) (mcg hr/mL) AUC (0-inf) (mcg hr/mL)=area under the plasma concentration-time profile extrapolated to infinity. C max (mcg/mL) Cmax (mcg/mL)=maximum observed plasma concentration.
T max (h) Tmax (h)= time to Cmax. 125 mg 2.24 0.8 0.9 250 mg 4.48 1.6 0.9 500 mg 8.95 3.3 0.9 1000 mg 17.9 6.6
0.9Following oral single-dose administration of 500 mg famciclovir to 7 patients with herpes zoster, the AUC (mean ± SD), C max , and t max were 12.1±1.7 mcg hr/mL, 4.0±0.7 mcg/mL, and 0.7±0.2 hours, respectively. The AUC of penciclovir was approximately 35% greater in patients with herpes zoster as compared to healthy volunteers. Some of this difference may be due to differences in renal function between the 2 groups.
There is no accumulation of penciclovir after the administration of 500 mg famciclovir three times daily for 7 days. Penciclovir C max decreased approximately 50% and t max was delayed by 1.5 hours when a capsule formulation of famciclovir was administered with food (nutritional content was approximately 910 Kcal and 26% fat). There was no effect on the extent of availability (AUC) of penciclovir.
There was an 18% decrease in C max and a delay in t max of about 1 hour when famciclovir was given 2 hours after a meal as compared to its administration 2 hours before a meal. Because there was no effect on the extent of systemic availability of penciclovir, famciclovir can be taken without regard to meals. Distribution: The volume of distribution (Vdβ) was 1.08±0.17 L/kg in 12 healthy male subjects following a single intravenous dose of penciclovir at 400 mg administered as a 1-hour intravenous infusion.
Penciclovir is less than 20% bound to plasma proteins over the concentration range of 0.1 to 20 mcg/mL. The blood/plasma ratio of penciclovir is approximately 1. Metabolism: Following oral administration, famciclovir is deacetylated and oxidized to form penciclovir.
Metabolites that are inactive include 6-deoxy penciclovir, monoacetylated penciclovir, and 6-deoxy monoacetylated penciclovir (5%, less than 0.5% and less than 0.5% of the dose in the urine, respectively). Little or no famciclovir is detected in plasma or urine. An in vitro study using human liver microsomes demonstrated that cytochrome P450 does not play an important role in famciclovir metabolism.
The conversion of 6-deoxy penciclovir to penciclovir is catalyzed by aldehyde oxidase. Cimetidine and promethazine, in vitro inhibitors of aldehyde oxidase, did not show relevant effects on the formation of penciclovir in vivo [see Drug Interactions ( 7.2 )]. Elimination: Approximately 94% of administered radioactivity was recovered in urine over 24 hour…
🧬 Mechanism of Action ▾
12.1Mechanism of Action Famciclovir is an orally administered prodrug of the anti-alpha herpes viral agent penciclovir [ see Microbiology ( 12.4 )].
📦 How Supplied / Storage and Handling ▾
16 HOW SUPPLIED/STORAGE AND HANDLING Famciclovir tablets, USP are supplied as film-coated tablets as follows: 500 mg in bottles of 21, 30, 60, and 90 tablets. • Famciclovir tablets, USP 500 mg: White to off white, oval film-coated, biconvex, engraved with "ML 72" on one side and plain on the other side. 500 mg 21's .....................................NDC 71205-609-21 500 mg 30's .....................................NDC 71205-609-30 500 mg 60's .....................................NDC 71205-609-60 500 mg 90's .....................................NDC 71205-609-90 Store at 20° - 25°C (68°-77°F); excursions permitted to 15°-30°C (59°-86°F) [see USP Controlled Room Temperature].
Preserve in tight containers. Store at controlled room temperature.
📋 Description ▾
11 DESCRIPTION The active ingredient in famciclovir tablets, USP is famciclovir, USP an orally administered prodrug of the antiviral agent penciclovir. Chemically, famciclovir is known as 2-[2-(2-amino-9 H -purin-9-yl)ethyl]-1,3-propanediol diacetate. Its molecular formula is C 14 H 19 N 5 O 4 ; its molecular weight is 321.3.
It is a synthetic acyclic guanine derivative and has the following structure: Famciclovir, USP is a white to pale yellow solid. It is freely soluble in acetone and methanol, and sparingly soluble in ethanol and isopropanol. At 25°C famciclovir, USP is freely soluble (greater than 25% w/v) in water initially, but rapidly precipitates as the sparingly soluble (2% to 3% w/v) monohydrate.
Famciclovir, USP is not hygroscopic below 85% relative humidity. Partition coefficients are: octanol/water (pH 4.8) P=1.09 and octanol/phosphate buffer (pH 7.4) P=2.08. Famciclovir tablets contain 125 mg, 250 mg, or 500 mg of famciclovir, USP together with the following inactive ingredients: hydroxypropyl cellulose, hypromellose, anhydrous lactose, magnesium stearate, polyethylene glycols, sodium starch glycolate and titanium dioxide.
Meets USP Dissolution Test 2. 123
💬 Information for Patients ▾
17 PATIENT COUNSELING INFORMATION Advise the patient to read the FDA-approved patient labeling (Patient information) There is no evidence that famciclovir will affect the ability of a patient to drive or to use machines. However, patients who experience dizziness, somnolence, confusion or other central nervous system disturbances while taking famciclovir tablets should refrain from driving or operating machinery. Because famciclovir tablets contains lactose (Famciclovir 125 mg, 250 mg and 500 mg tablets contain lactose 25.97 mg, 51.95 mg and 103.90 mg, respectively), patients with rare hereditary problems of galactose intolerance, a severe lactase deficiency or glucose-galactose malabsorption should be advised to discuss with their healthcare provider before taking famciclovir tablets.
Herpes Labialis (Cold Sores) Patients should be advised to initiate treatment at the earliest sign or symptom of a recurrence of cold sores (e.g., tingling, itching, burning, pain, or lesion). Patients should be instructed that treatment for cold sores should not exceed 1 dose. Patients should be informed that famciclovir tablets are not a cure for cold sores.
Genital Herpes Patients should be informed that famciclovir tablets are not a cure for genital herpes. There are no data evaluating whether famciclovir tablets will prevent transmission of infection to others. Because genital herpes is a sexually transmitted disease, patients should avoid contact with lesions or intercourse when lesions and/or symptoms are present to avoid infecting partners.
Genital herpes is frequently transmitted in the absence of symptoms through asymptomatic viral shedding. Therefore, patients should be counseled to use safer sex practices. If episodic therapy for recurrent genital herpes is indicated, patients should be advised to initiate therapy at the first sign or symptom of an episode.
There are no data on safety or effectiveness of chronic suppressive therapy of longer than 1-year duration. Herpes Zoster (Shingles) There are no data on treatment initiated more than 72 hours after onset of zoster rash. Patients should be advised to initiate treatment as soon as possible after a diagnosis of herpes zoster.
All brand names listed are the registered trademarks of their respective owners and are not trademarks of the Macleods Pharmaceutical Ltd. Manufactured for Macleods Pharma USA, INC, Plainsboro, NJ 08536 Manufactured by: Macleods Pharmaceutical Limited Daman (U.T.), INDIA Repackaged by: Proficient Rx LP Thousand Oaks, CA 91320 Revised: July 2020 .