Acyclovir (Zovirax) is an antiviral drug that is used to treat genital and oral herpes simplex virus infections. It is also used to treat varicella-zoster virus infection, including herpes encephalitis. It is also used to prevent the reactivation of herpes simplex virus reactivation in HIV-positive patients, neutropenic patients, and patients who have undergone hematopoietic stem cell transplantation.  It is also used in the prevention of varicella-zoster virus and cytomegalovirus reactivation in patients with allogeneic hematopoietic stem cell transplantation.

Acyclovir resistant herpes infections:

Acyclovir resistance is very rare and affects less than 1% of all cases. Resistance is common in patients who are on long-term prophylactic treatment for recurrent oral or genital herpes infections and patients undergoing hematopoietic stem cell transplantation. Up to 95% of the HSV becomes resistant via mutation of the viral thymidine kinase gene. Alternative agents should be used in such cases. These include Foscarnet, brincidofovir (CMX001), valomaciclovir, and n-methanocarbathymidine [Ref]. One case report of a young female was successfully treated with continuous acyclovir infusion [Ref]

Acyclovir for Cold Sores (Herpetic gingivostomatitis) in Children:

Cold Sores or Herpetic Gingivostomatitis affects mostly children younger than 6 years of age. It presents as pain, redness, blisters, crusting, and bleeding. Treatment is usually supportive in the form of hydration, pain relief, and anti-allergics. However, severe cases may lead to dehydration, superimposed bacterial infections, and encephalitis. It is highly contagious and may be recurrent in some cases. Acyclovir treatment has been found to be effective especially if the treatment is initiated within 48 hours of the cold sores. Compared to supportive treatment alone, the addition of acyclovir results in the rapid resolution of symptoms of pain, cold sores, and recurrence of the disease [Ref].

Acyclovir for warts:

Acyclovir cream has little therapeutic benefits in the treatment of warts. However, one patient with plantar warts that were resistant to conventional therapy improved dramatically with a ten days course of oral acyclovir. Althought the treatment was intended for shingles in this case, the authors concluded that the efficacy of oral acyclovir must be investigated in clinical trials for warts [Ref].

Acyclovir Contraindications:

• Acyclovir is contraindicated in patients who are allergic to acyclovir, valacyclovir, or any component of the formulation.

Acyclovir Warnings & Precautions

• Acyclovir can be fatal in the kidneys and is considered nephrotoxic.
• Patients who are dehydrated, on nephrotoxic medications or have a pre-existing kidney disease are particularly at risk.
• Patients at high risk should receive the drug in an intravenous drip over a minimum of one hour.
• Patients with immunocompromised may experience thrombotic and hemolytic uremic purpura or hemolytic uremic syndrome after receiving acyclovir.

Acyclovir Dose in Adults

Acyclovir dose for Genital herpes simplex virus (HSV) infection:

• Immunocompetent patients with a severe episode should be given acyclovir intravenously at a dose of 5 mg/kg/dose every 8 hours for 5-7 days followed by oral therapy to complete a ten days course.
• In less severe cases,
  • Oral acyclovir at a dose of 200 mg five times a day for ten days, or
  • 400 mg thrice daily for 7-10 days.

Alternatively, the following regimens may also be given as recommended by the CDC:

• 400 mg thrice daily for 5 days;
• 800 mg twice daily for 5 days;
• 800 mg thrice daily for 2 days

For Chronic suppression of the virus:

• 400 mg two times a day or 200 mg 3-5 times daily, for up to 12 months may be given followed by re-evaluation.

Acyclovir dosage for Herpes zoster (shingles):

• Immunocompetent patients:

  • Oral acyclovir 800 mg 5 times daily for 7-10 days

• Immunocompromised patients:

  • Intravenous 10 mg/kg/dose or 500 mg/m 2 /dose three times a day for 7 days

Acyclovir for Herpes simplex virus encephalitis: 

• 10 mg/kg/dose intravenously thrice daily for 10 days
• Some clinicians also recommend 10-15 mg/kg/dose thrice daily for 14-21 days.

Mucocutaneous Herpes simplex virus infection:

• Recommended in Immunocompromised patients:

  • 5 mg/kg/dose intravenously every thrice daily for 7 days.
  • It may be given for 14 days in severe cases.
  • 400 mg orally 5 times a day for 7 days may be given in less severe cases.

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Acyclovir for Orolabial Herpes Simplex Virus infection: 

• Dosage in immunocompetent individuals:

  • 200-400 mg 5 times daily for 5 days for episodic or recurrent infection treatment;
  • Patients with a first episode may not be treated or maybe advised 200 mg tablets five times daily for 5-7 days.

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Acyclovir for Varicella-zoster (chickenpox): 

(Note: Treatment should begin within the first 24 hours of rash onset).

• Oral tablets in immunocompetent patients >40 kgs:

  • 800 mg 4 times daily for 5 days

• Immunocompromised patients:

  • 10 mg/kg/dose intravenous thrice daily for 7 days.

• CDC HIV guidelines in immunocompromised individuals:

  • 10-15 mg/kg/dose thrice daily for 7-10 days.

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Acyclovir for the prevention of Herpes Simplex Virus reactivation in HIV-positive patients: 

• 400-800 mg orally twice or thrice daily

Acyclovir for the prevention of HSV reactivation in Hematopoietic Stem Cell Transplantation: 

Note: Start Acyclovir at the beginning of conditioning therapy and continue until mucositis resolves or engraftment for about 30 days

• 200 mg 8 hourly orally or
• 250 mg/m 2 /dose intravenous every twice daily.

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Acyclovir for the prevention of Varicella zoster virus reactivation in allogeneic hematopoietic stem cell transplantation: 

• 800 mg orally twice daily.

Acyclovir Dose in Childrens

Acyclovir dose in neonates:

• For the treatment of Herpes Simplex Virus infection:

  • 20 mg/kg/dose intravenous thrice daily
  • for 21 days in CNS and disseminated infections.
  • for 14 days in the skin and mucous membrane infections

• Acyclovir for chronic suppression of Herpes Simplex Virus infection following CNS infection or disseminated infection:

  • AAP Recommendation: 300 mg/m 2 /dose per oral thrice daily after the completion of a 14- to 21-day-course of intravenous therapy for 6 months.

Acyclovir for the treatment of Varicella zoster virus infection:

• 10-15 mg/kg/dose thrice daily for 5-10 days.
• It should be continued for 48 hours or more after the last new lesions have appeared.

Acyclovir for HSV infection:

• For the treatment of disseminated, CNS, or skin, eye, or mouth disease:

  • Infants 1-3 months:

    • 20 mg/kg/dose thrice daily intravenously
    • for 14 days in cutaneous, skin, mouth and eye infection
    • for 21 days in CNS or disseminated infection

For Chronic suppressive therapy after severe disseminated and neurological infections, the AAP recommends 300 mg/m 2 thrice daily after the completion of a 14- to 21-days-of intravenous course.

Acyclovir for the treatment of HSV encephalitis:

• Infants and Children 3 months to <12 years:

  • Immunocompetent (Non-HIV-exposed):

    • 10-15 mg/kg/dose thrice daily for 14 to 21 days.

  • HIV-exposed/-positive:

    • 10 mg/kg/dose thrice daily for 21 days.
    • The therapy should be continued until the repeat CSF HSV DNA PCR is negative.

• Children ≥12 years and Adolescents:

  • Immunocompetent (Non-HIV-exposed):

    • 10 mg/kg/dose thrice daily for 14-21 days.

  • HIV-exposed or positive:

    • 10 mg/kg/dose thrice daily for 21 days

Acyclovir for Genital infection due to HSV infection:

• Immunocompetent (Non-HIV-exposed/-positive):

  • Children less than 12 years of age:

    • 40-80 mg/kg/ day divided into 3 or 4 doses per day for 5-10 days.
    • The maximum daily dose is 1000 mg/day)

  • Children and Adolescents 12 years of age or more:

    • 200 mg 5 times daily or 400 mg thrice daily for 7-10 days.

• HIV-exposed or positive:

  • Children less than 45 kg:

    • 20 mg/kg/dose thrice daily for 5-14 days (maximum dose: 400 mg)

  • Children weighing 45 kg or more and Adolescents:

    • 400 mg 2-3 times daily for 5-14 days

• For severe infection independent of HIV status:

  • Children and Adolescents 12 years of age or more:

    • 5 mg/kg/dose thrice daily for 5-7 days.

• Recurrent oral infection:

  • Children less than 12 years:

    • 10 mg/kg/dose thrice daily for up to 12 months (maximum daily dose: 1000 mg/ day)

  • Children and Adolescents 12 years of age or more:

    • 200 mg every 5 times a day or 800 mg twice daily for 5 days or 800 mg thrice daily for 2 days.

• For chronic suppression:

• Immunocompetent (Non-HIV-exposed/-positive):

  • Children less than 12 years of age:

    • 40-80 mg/kg/ day thrice daily for up to 12 months.
    • The maximum daily dose is 1000 mg/ day

  • Children and Adolescents 12 years of age or more:

    • 400 mg twice daily for up to 12 months.

• HIV-exposed/-positive:

  • Infants and Children:

    • 20 mg/kg/dose twice daily.
    • The maximum dose is 400 mg

  • Adolescents:

    • 400 mg twice daily.

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Acyclovir for HSV gingivostomatitis in HIV-exposed/-positive patients:

• For mild infections:

  • Infants and Children:
    • 20 mg/kg/dose per oral thrice daily for 5-10 days.
    • The maximum dose is 400 mg

• Moderate to severe infections:

  • Infants and Children:
    • 5-10 mg/kg/dose intravenous thrice daily.

Acyclovir for recurrent and chronic suppressive therapy of herpes labialis (cold sore): 

• Children:

  • 30 mg/kg/ day in 3 divided doses per oral for up to 12 months.
  • The maximum daily dose is 1000 mg/ day.

Acyclovir for cutaneous HSV infection in immunocompromised patients:

• Infants, Children, and Adolescents:

  • 10 mg/kg/dose intravenous thrice daily for 7-14 days.

• Children 2 years of age or more and Adolescents:

  • 1000 mg/ day per oral in 3-5 divided doses for 7-14 days.
  • The maximum daily dose should not exceed 80 mg/kg/day

Acyclovir for Suppression of chronic ocular or cutaneous infections:

• Infants and Children in HIV-exposed patients:

  • 20 mg/kg/dose twice daily for 5-14 days; (maximum dose: 400 mg)

• Children and Adolescents 12 years of age or more independent of HIV status:

  • 400 mg twice daily for up to 12 months.

Acyclovir for the Treatment of Severe HSV progressive or disseminated infection in an immunocompromised host including HIV positive individuals:

• Infants, Children, and Adolescents:

  • 10 mg/kg/dose thrice daily for 21 days.

Acyclovir for the prophylaxis of Varicella zoster (chickenpox or shingles) in HIV-exposed/-positive:

• Infants and Children:

  • 20 mg/kg/dose 4 times daily per oral for 5-7 days (maximum dose: 800 mg)

• Adolescents:

  • 800 mg 5 times a day per oral for 5 days.

Acyclovir for the treatment of shingles or Varicella zoster virus infection:

• Children, 12 years of age or more:

  • 800 mg 5 times a day for 5-7 days.

• Hospitalized patients:

  • Intravenous Acyclovir 10 mg/kg/dose thrice daily for 7 days.

• HIV-exposed or positive patients with a mild to moderate uncomplicated disease: 

  • 20 mg/kg/dose five times daily for 7-10 days (maximum dose: 800 mg).

• Adolescents:

  • 800 mg 5 times daily for 5-7 days.
  • Patients with severe disease marked immunosuppression or multifocal disease and those with trigeminal nerve involvement should be given an intravenous dose of 10 mg/kg thrice daily for 10-14 days.

Acyclovir for the treatment of acute retinal necrosis caused by Varicella Zoster  in HIV-exposed individuals:

• Infants:

  • 10-15 mg/kg/dose thrice daily for 10-14 days followed by oral acyclovir

• Children:

  • 10-15 mg/kg/dose or 500 mg/m 2 /dose thrice daily for 10-14 days followed by oral acyclovir or valacyclovir.

• Adolescents:

  • 10 mg/kg/dose thrice daily for 10-14 days, followed by oral valacyclovir.

Patients should be given a maintenance dose of oral acyclovir 20 mg/kg/dose thrice daily for a total of 4-6 weeks.

Acyclovir dose in renal disease: 

• CrCl of 10-25 mL/minute/1.73 m 2:

  • Patients who require 800 mg 5 times daily should be given 800 mg thrice daily.

• CrCl of less than 10 mL/minute/1.73 m 2 :

  • Patients who require 200 mg 5 times daily or 400 mg twice daily should be given 200 mg twice daily.
  • Patients who require 800 mg 5 times daily should be given 800 mg twice daily.

Acyclovir Intravenous dose in renal disease:

• CrCl of 25-50 mL/minute/1.73 m 2 :

  • The usual dose should be given twice daily.

• CrCl of 10-25 mL/minute/1.73 m 2 :

  • The usual dose should be given once daily

• CrCl of less than 10 mL/minute/1.73 m 2 :

  • Give half the recommended dose once daily.

• Intermittent thrice-weekly hemodialysis (IHD) (administer after hemodialysis on dialysis days):

  • 2.5-5 mg/kg every 24 hours

• Peritoneal dialysis (PD):

  • Administer 50% of the dose once daily; no supplemental dose needed

• CVVH:

  • 5-10 mg/kg intravenous every 24 hours

• CVVHD/ CVVHDF:

  • 5-10 mg/kg intravenous every 12-24 hours

Acyclovir dose in liver disease:

• No dose adjustment is required in liver diseases but should be used with caution in advanced liver disease.

How to administer Acyclovir?

• Oral Acyclovir may be administered with or without food. Intravenous acyclovir should be infused over 1 hour to prevent renal damage.
• A rapid intravenous infusion should be avoided, as well as an intramuscular and subcutaneous injection.
• It is Stable in D 5 W and  NS and Incompatible with blood products and protein-containing solutions.
• It is also Incompatible with Caffeine citrate, ceftriaxone, and pantoprazole.

Pregnancy Risk Factor B

• Birth defects are not known to exist, but Acyclovir has been proven to cross the placental barrier.
• According to the CDC, acyclovir can be used by pregnant women with genital herpes.

Use during breastfeeding:

• AAP states that Acyclovir can be used during breastfeeding, but it is not compatible with breastmilk.

Acyclovir Side Effects (Severe):

Rapid severe side effects:

• Anaphylactoid reactions,
• angioedema,

Early severe side effects:

• Coma,
• tissue necrosis,
• visual impairment,

Delayed severe side effects:

• Seizures,
• renal tubular obstruction,
• azotemia,
• renal failure,
• Stevens-Johnson syndrome,
• erythema multiforme,
• toxic epidermal necrolysis,
• hemolytic-uremic syndrome,
• thrombotic thrombocytopenic purpura (TTP),
• vasculitis,
• disseminated intravascular coagulation (DIC).

Acyclovir Side effects (Moderately severe):

Rapid side effects:

• Phlebitis,
• hypotension,

Early side effects:

• Hallucinations,
• confusion,
• erythema,
• delirium,
• psychosis,
• hemolysis

Delayed side effects:

• Elevated hepatic enzymes,
• Encephalopathy,
• Anemia,
• thrombocytopenia,
• neutropenia,
• thrombocytosis,
• stomatitis,
• crystalluria,
• ataxia,
• dysarthria,
• hepatitis,
• hyperbilirubinemia,
• jaundice,
• edema,
• contact dermatitis,
• peripheral edema,
• leukopenia,
• hematuria, and
• lymphadenopathy.

Acyclovir Side effects (Mild):

Rapid side effects:

• Injection site reactions,
• pruritis,
• urticaria,

Early side effects:

• Skin irritation,
• malaise,
• nausea,
• vomiting,
• diarrhea,
• headache,
• rash,
• lethargy,
• tremor,
• dizziness,
• agitation,
• drowsiness,
• fatigue,
• abdominal pain,
• fever, and
• myalgia

Delayed side effects:

• Leukocytosis,
• paresthesias,
• anorexia,
• photosensitivity,
• xerosis, and
• alopecia.

Contraindication to Acyclovir (Zovirax):

Hypersensitivity to acyclovir, valacyclovir, or any component of the formulation

Warnings and Precautions

• Extravasation:

  • Acyclovir can cause severe tissue necrosis when administered intravenously. Extravasation into the subcutaneous tissue should be avoided.

• Varicella:

  • Appropriate use:
    • For the treatment of chickenpox (Varicella), it is best to start acyclovir treatment within 24 hours of symptoms onset.
    • The intravenous route is the preferred one. For the treatment of varicella, oral administration is not recommended, however, patients who are at an increased risk of severe infection may also be given oral acyclovir.
    • Children at increased risk of a severe infection include:
      • Those aged 12 years or older
      • Patients with chronic skin or pulmonary disorder
      • patients on long-term aspirin or salicylate therapy, and
      • patients on corticosteroids therapy

Monitoring Parameters:

• Blood CP,
• Urinalysis,
• Renal function tests, and
• Liver Function Tests

Acyclovir Mechanism Of Action:

It interferes with DNA synthesis and viral reproduction by competing for deoxyguanosine Triphosphate for viral DNA Polymerase.

Absorption: It can be taken orally. Only 15% to 30% of the drug is available when the drug is taken orally.

Distribution: It is widely available and distributed in the body, including the brain, kidneys, liver, lungs, and spleen.

Plasma Protein binding: The drug will be bound to plasma proteins anywhere from 9% to 33%.

Bioavailability: It has a bioavailability of 10% to 20%

Half-life elimination: It takes 4 hours for neonates, 2-3 hours for children 1-12 years old, and 3 hours for adults.

Peak Serum concentration: The time to get there to Peak levels is about 1.5-2 hours.

It is excreted primarily via urine

Acyclovir Brand Names in Pakistan:

ACEFAS (FASSGEN PHARMACEUTICALS)

Tablets : 200 mg :

10 tablets pack: Rs. 200.00

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ACICLOVIR (R.Y. INTERNATIONAL)

Tablets : 200 mg :

25 tablets pack : Rs. 1035.00

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ACLOVA (AKHAI PHARMACEUTICALS)

Vials : 250 mg/vial :

5 Vials pack : Rs. 2143.80

Tablets : 200 mg :

10 tablets pack : Rs. 396.00

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ACYLEX (FEROZSONS LABORATOIES LTD)

Ointment : 5 %w/w :

5 gram pack : Rs. 55.00

Suspension : 200 mg/5 ml :

60 ml pack : Rs. 165.00

Tablets : 800 mg :

10 tablets pack : Rs. 320.00

Tablets : 400 mg :

20 tablets pack : Rs.  375.00

Tablets : 200 mg :

25 tablets pack : Rs. 260.00

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ACYROVIN (21ST CENTURY PHARMACEUTICALS CO)

Tablets : 200 mg :

100 tablets pack : Rs. 1980.00

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CLOVIR (GLITZ PHARMA)

Tablets : 400 mg :

35 tablets pack : Rs.  1120.00

Tablets : 200 mg :

10 tablets pack : Rs. 200.00

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CLOVIREX (BROOKES PHARMACEUTICAL LABORATORIES (PAK) LTD)

Tablets : 800 mg :

20 tablets pack : Rs.  500.00

Tablets : 200 mg :

10 tablets pack : Rs. 100.00

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CYCLOR (CANDID PHARMACEUTICALS)

Tablets : 400 mg :

25 tablets pack : Rs.  1120.00

Tablets : 200 mg :

10 tablets pack : Rs. 200.00

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CYCLOZ (HIGHNOON LABORATORIES LTD)

Eye ointment : 3 %w/w :

5 gram pack : Rs. 152.00

Suspension : 200 mg/5 ml :

60 ml pack : Rs. 165.00

Tablets : 800 mg :

25 tablets pack : Rs. 1000.00

Tablets : 400 mg :

25 tablets pack : Rs.  550.00

Tablets : 200 mg :

25 tablets pack : Rs. 914.00

Cream : 5 %w/w :

10 gram pack : Rs. 255.00

Vials : 250 mg/vial :

5 vials pack : Rs. 1914.00

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ELOVIR (SIZA INTERNATIONAL (PVT) LTD)

Tablets : 200 mg :

20 tablets pack : Rs. 119.00

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MEDIRAX (MEDIATE PHARMACEUTICALS (PVT) LTD)

Tablets : 200 mg :

10 tablets pack : Rs. 200.00

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VIRUCID (SPENCER PHARMA)

Tablets : 400 mg :

25 tablets pack : Rs.  1120.00

Tablets : 200 mg :

10 tablets pack : Rs. 200.00

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VIVER (WNS FIELD PHARMACEUTICALS)

Tablets : 200 mg :

10 tablets pack : Rs. 200.00

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ZORAXIN (VALOR PHARMACEUTICALS)

Ointment : 3 %w/w :

4.5 gram pack : Rs. 141.00

Tablets : 800 mg :

10 tablets pack : Rs. 220.00

Tablets : 400 mg :

20 tablets pack : Rs.  366.00

Tablets : 200 mg :

20 tablets pack : Rs. 217.00

Cream : 5 %w/w :

10 gram pack : Rs. 98.00

2 gram pack : Rs. 35.00

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ZOVIRAX (GLAXOSMITHKLINE)

Cream : 5 %w/w :

10 gram pack : Rs. 824.00

2 gram pack : Rs. 35.00

Tablets : 200 mg :

25 tablets pack : Rs. 1749.00

Eye ointment : 3 %w/w :

4.5 gram pack : Rs. 241.00

Vials : 250 mg/vial :

5 vials pack : Rs. 2377.00

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VIROCIL (SHROOQ PHARMACEUTICALS)

Tablets : 800 mg :

20 tablets pack : Rs. 720.00

Tablets : 400 mg :

35 tablets pack : Rs. 1120.00

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ADEOWIN (ORTA LABS (PVT) LTD)

Tablets : 10 mg :

30 tablets pack : Rs. 6000.00

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DFOVIR (ENGLISH PHARMACEUTICALS INDUSTRIES)

Tablets : 10 mg :

30 tablets pack : Rs. 6000.00

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ZACLOVIR (ZAFA PHARMACEUTICAL LABORATORIES (PVT) LTD)

Capsules : 200 mg :

25 capsules pack : Rs. 324.00

Cream : 5%w/w :

10 gram pack : Rs. 122.00

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CLOVIREX TOPICAL (BROOKES PHARMACEUTICAL LABORATORIES (PAK) LTD)

Cream : 5 %w/w :

10 gram pack : Rs. 100.00

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HERPIRID (DERMA TECHNO PAKISTAN)

Cream : 5 %w/w :

4 gram pack : Rs. 145.00

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ACYWEL (ZEB LABORATORIES)

Ointment : 5 %w/w :

5 gram pack : Rs. 85.00

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VIROLITE (PEARL & PEARL)

Ointment : 5 %w/w :

10 gram pack : Rs. 170.00

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ACYCLOVIR (HAJI MEDICINE CO)

1 injection : Rs. 426.60

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HERPESIN (UMAIR ASSOCIATES)

Injection : 250 mg/vial :

1 injection : Rs. 540.60

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VIRQ (WILSHIRE LABORATORIES (PVT) LTD)

Injection : 250 mg/vial :

1 injection : Rs. 390.60

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KLOVIR (ROTEX MEDICA PAKISTAN (PVT) LTD)

Injectin : 500 mg :

1 injection pack : Rs. 650.00

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ACYCLOVIR (ABBOTT LABORATORIES (PAKISTAN) LIMITED)

Injection : 500 mg/vial :

10 ml injection : Rs. 985.00

Acyclovir Brand Names (International):

• Acic
• Aciclodan
• Aciclor
• Aciclosina
• Acicvir
• Aciherpin
• Acihexal
• Acivir Eye
• Acivirex
• Aclovir
• ACS
• Activir
• Acyclo-V
• Acyclovenir
• Acylene
• Acyrax
• Acyvir
• Aisike
• Aisile
• Antix
• Asile
• Avir
• Avorax
• Bearax
• Biraxin
• Cicloferon
• Cicloviral
• Ciclox
• Clinovir
• Clopes
• Clovika
• Clovir
• Covelay
• Cusiviral
• Cyclivex
• Cycloherp
• Cyclostad
• Cyclovir
• Cyllanvir
• Deherp
• Docaciclo
• Dravyr
• Duvimex
• Ecuvir
• Entir
• Erlvirax
• Euroclovir
• Eurovir
• Expit
• Geavir
• Helvevir
• Herax
• Herpesin
• Herpetad
• Herpevex
• Herpevir
• Herpex
• Herpizyg
• Heviran
• Lermex
• Licovir
• Lisovyr
• Lovir
• Lovire
• Marvir
• Medovir
• Molavir
• Norum
• Ozvir
• Poviral
• Qualiclovir
• Ranvir
• Reclovax
• Remex
• Skirax
• Vacrax
• Vermis
• Viralex-DS
• Viratop
• Virax
• Virest
• Virex
• Virless
• Viroclear
• Virogon
• Viromed
• Virzin
• Vivir
• Zevin
• Zodiac
• Zoral
• Zorax
• Zorexin
• Zoter
• Zoteran
• Zovir
• Zovirax
• Zoylex
• Zyvir