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Brand Name :
Zovirax
Synonyms :
Aciclovir, Aciclovirum, Acycloguanosine, acyclovir
Class :
Antiviral, Chemotherapeutics, Other; Antivirals, HSV; Antivirals, VZV
Brand Name :
Zovirax
Synonyms :
Aciclovir, Aciclovirum, Acycloguanosine, acyclovir
Class :
Antiviral, Chemotherapeutics, Other; Antivirals, HSV; Antivirals, VZV
Adult
Dosage Forms & Strengths
Capsule
200 mg
Injectable solution
50 mg/mL
Suspension (oral)
200 mg/5 mL
Injection (lyophilized powder for reconstitution)
500 mg/vial
1000 mg/vial
Tablet
400 mg
800 mg
Intravenous (IV) administration of 10-15 mg/kg every 8 hours for 10 days; reports of up to 14–21 days
Dose Adjustments
Renal dose adjustments
dose modification in accordance with standard dosage guidelines and renal clearance
200 milligrams every four hours:
200 mg every 12 hours; 0–10 mL/min/1.73 m²
More than 10 mL/min/1.73 m²: 200 mg five times a day every four hours
400 mg every 12 hours :
200 mg every 12 hours for 0–10 mL/min/1.73 m²
Exceeding 10 mL/min/1.73 m²: 400 mg per 12-hour period
800 mg every 4 hours :
0–10 mL/min/1.73 m²: 800 mg every 12 hours
800 mg every 8 hours at 10–25 mL/min/1.73 m²
More than 25 mL/min/1.73 m²: 800 mg five times a day every four hours
Changing the dosage according to the dosage form:
Renal impairment (IV)
Administer prescribed dose every 12 hours when CrCl is 25–50 mL/min/1.73 m²
10–25 mL/min/1.73 m² of CrCl: Administer the prescribed dosage once every 24 hours
Give 50% of the recommended dose every 24 hours if the CrCl is less than 10 mL/min/1.73 m²
Renal impairment (Oral)
When the CrCl is less than 10 mL/min/1.73 m², the normal dosage of 200 mg every 4 hours or 400 mg every 12 hours should be reduced to 200 mg every 12 hours
CrCl 10–25 mL/min/1.73 m² and the usual dosage of 800 mg every 4 hours: Reduce to 800 mg every 8 hours
If the CrCl is less than 10 mL/min/1.73 m², reduce the normal dosage to 800 mg every 12 hours
For those over 40 kg (immunocompetent), take 800 mg orally every 6 hours for a period of 5 days.
Patients with impaired immune systems: 10–15 mg/kg IV every 8 hours for 7–10 days
Use ideal body weight while treating obese individuals (IBW)
Dose Adjustments
Renal dose adjustments
dose modification in accordance with standard dosage guidelines and renal clearance
200 milligrams every four hours:
200 mg every 12 hours; 0–10 mL/min/1.73 m²
More than 10 mL/min/1.73 m²: 200 mg five times a day every four hours
400 mg every 12 hours :
200 mg every 12 hours for 0–10 mL/min/1.73 m²
Exceeding 10 mL/min/1.73 m²: 400 mg per 12-hour period
800 mg every 4 hours :
0–10 mL/min/1.73 m²: 800 mg every 12 hours
800 mg every 8 hours at 10–25 mL/min/1.73 m²
More than 25 mL/min/1.73 m²: 800 mg five times a day every four hours
Changing the dosage according to the dosage form:
Renal impairment (IV)
Administer prescribed dose every 12 hours when CrCl is 25–50 mL/min/1.73 m²
10–25 mL/min/1.73 m² of CrCl: Administer the prescribed dosage once every 24 hours
Give 50% of the recommended dose every 24 hours if the CrCl is less than 10 mL/min/1.73 m²
Renal impairment (Oral)
When the CrCl is less than 10 mL/min/1.73 m², the normal dosage of 200 mg every 4 hours or 400 mg every 12 hours should be reduced to 200 mg every 12 hours
CrCl 10–25 mL/min/1.73 m² and the usual dosage of 800 mg every 4 hours: Reduce to 800 mg every 8 hours
If the CrCl is less than 10 mL/min/1.73 m², reduce the normal dosage to 800 mg every 12 hours
Acute treatment: 800 mg taken orally five times a day (7–10) for four hours each time you're awake
patients with weakened immune systems:
Intravenous 10 mg/kg every 8 hours for 7 days
Use ideal body weight while treating obese individuals (IBW):
Full recommended IV dose every 12 hours (CrCl 25–50 mL/min)
CrCl 10–25 mL/min: Once daily, provide the entire prescribed IV dosage
CrCl 0–10 mL/min: 50% of the suggested daily IV dosage
Dose Adjustments
Renal dose adjustments
dose modification in accordance with standard dosage guidelines and renal clearance
200 milligrams every four hours:
200 mg every 12 hours; 0–10 mL/min/1.73 m²
More than 10 mL/min/1.73 m²: 200 mg five times a day every four hours
400 mg every 12 hours :
200 mg every 12 hours for 0–10 mL/min/1.73 m²
Exceeding 10 mL/min/1.73 m²: 400 mg per 12-hour period
800 mg every 4 hours :
0–10 mL/min/1.73 m²: 800 mg every 12 hours
800 mg every 8 hours at 10–25 mL/min/1.73 m²
More than 25 mL/min/1.73 m²: 800 mg five times a day every four hours
Changing the dosage according to the dosage form:
Renal impairment (IV)
Administer prescribed dose every 12 hours when CrCl is 25–50 mL/min/1.73 m²
10–25 mL/min/1.73 m² of CrCl: Administer the prescribed dosage once every 24 hours
Give 50% of the recommended dose every 24 hours if the CrCl is less than 10 mL/min/1.73 m²
Renal impairment (Oral)
When the CrCl is less than 10 mL/min/1.73 m², the normal dosage of 200 mg every 4 hours or 400 mg every 12 hours should be reduced to 200 mg every 12 hours
CrCl 10–25 mL/min/1.73 m² and the usual dosage of 800 mg every 4 hours: Reduce to 800 mg every 8 hours
If the CrCl is less than 10 mL/min/1.73 m², reduce the normal dosage to 800 mg every 12 hours
Dosage Forms & Strengths
Capsule
200 mg
Injectable solution
50 mg/mL
Suspension (oral)
200 mg/5 mL
Injection (lyophilized powder for reconstitution)
500 mg/vial
ten00 mg/vial
Tablet
400 mg
800 mg
Children under 40 kg and 2 years old: 20 mg/kg/dose taken orally every 6 hours for 5 days, with a maximum dose of 800 mg
Use ideal body weight while treating obese individuals (IBW):
Over 40 kg: 800 mg taken orally every 6 hours for 5 days
In patients with impaired immune systems:
Less than 12 years old: intravenously (IV) administer 20 mg/kg/dose every 8 hours for 7 days
Elderly adults: 10 mg/kg/dose IV given every 8 hours for a period of 7 days
Children:
Immunocompromised children under 12 years old: 20 mg/kg IV every 8 hours for 7 days
Use ideal body weight while treating obese individuals (IBW):
If immunocompetent and older than 12 years old, take 800 mg orally every 4 hours while awake, five times a day for seven to ten days
Elderly (immunocompromised) than 12 years old: 30 mg/kg/day IV given every 8 hours for a duration of 7–10 days
Children aged three months to twelve years: IV 20 mg/kg every 8 hours for 10 days; reports of up to 14–21 days have been made
Youngsters older than 12: For 14–21 days, give 10-15 mg/kg IV every 8 hours
Use ideal body weight while treating obese individuals (IBW)
Refer to the adult dosingÂ
acyclovir: it may increase the risk of CNS depression
acyclovir: it may increase the risk of CNS depression
acyclovir: it may increase the risk of CNS depression
acyclovir: it may increase the risk of CNS depression
acyclovir: it may increase the risk of CNS depression
metabolism of acyclovir is reduced when taken with cinoxacin
amphotericin B deoxycholate and acyclovir both heighten ototoxicity and/or nephrotoxicity
both cidofovir and acyclovir exacerbate ototoxicity and/or nephrotoxicity
neomycin PO and acyclovir both cause increased ototoxicity and/or nephrotoxicity
acyclovir pharmacodynamically antagonizes talimogene laherparepvec to reduce its effects
By competing with acidic (anionic) drugs for renal clearance, acyclovir will raise the amount of probenecid
it may diminish the excretion rate when combined with gadofosveset, resulting in an enhanced serum level
acyclovir Might lead to a reduction in the rate of excretion of triethylenetetramine, potentially leading to elevated levels of serum
meticrane has the potential to enhance the rate of excretion of acrivastine; this can potentially lead to decreased levels of serum, possibly diminishing its effectiveness
When used with acyclovir, levobupivacaine's metabolism may be reduced
It may enhance the risk of bleeding when combined with nimesulide
acyclovir has the potential to reduce the rate of excretion of idebenone, leading to an elevation in levels of serum
Combining tegafur with acyclovir can reduce tegafur’s metabolism
When domeperidone and acyclovir is used together, this leads to reduction in the domeperidone’s metabolism
When acyclovir is used together with somatotropin, this leads to a rise in acyclovir’s metabolism
When acyclovir is used together with cephaloglycin, this leads to increased risk or seriousness of nephrotoxicity
When acyclovir is used together with ouabain, this leads to reduction in acyclovir excretion
When acyclovir is used together with promazine, this leads to a reduction in acyclovir metabolism
acyclovir has the potential to reduce the excretion rate of deferiprone, leading to an increased level of serum
When acyclovir is used together with droxicam, this leads to enhanced risk or seriousness of nephrotoxicity
acyclovir leads to a reduction in the rate of excretion of eucalyptus oil which leads to increased level of serum
acyclovir leads to a reduction in the rate of excretion of chromous sulfate, which leads to an increased level of serum
acyclovir leads to a reduction in the rate of excretion of pentaerythritol tetranitrate, which leads to an increased level of serum
the risk or severity of nephrotoxicity and hypocalcemia can increase when acyclovir is combined with alendronic acid
acyclovir leads to a reduction in the rate of excretion of potassium acetate, which leads to an increased level of serum
acyclovir leads to a reduction in the rate of excretion of potassium perchlorate, which leads to an increased level of serum
the excretion rate of ioxilan may be decreased by acyclovir, potentially resulting in a higher serum level
acyclovir leads to a reduction in the rate of excretion of nitric oxide, which leads to an increased level of serum
acyclovir may lower the excretion rate of phylloquinone, potentially leading to higher serum levels
muzolimine may raise the excretion rate of acyclovir, potentially resulting in a lower serum level and a potential reduction in efficacy
acyclovir may lowe the excretion rate of n-acetyl tyrosine, potentially resulting in elevated serum levels
acyclovir may lower the excretion rate of sulbactam, potentially resulting in a raised serum level
both cisplatin and acyclovir exacerbate ototoxicity and/or nephrotoxicity
by reducing renal clearance, acyclovir raises peramivir levels
the metabolism of doxofylline can be lowered when combined with acyclovir
choline magnesium trisalicylateÂ
the hazard or intensity of nephrotoxicity can be heightened when acyclovir is combined with Choline magnesium trisalicylate
lansoprazole amoxicillin and clarithromycin
when amoxicillin combines with acyclovir it decreases the effects of the action of drug by decreasing renal clearance
amoxicillin and clavulanate potassium
when amoxicillin combines with acyclovir it decreases the effects of the action of drug by decreasing renal clearance
omeprazole amoxicillin and clarithromycin
when both drugs are combined, there may be a decreased effect of the drug's action by decreasing renal clearance
when both drugs are combined, there may be a decreased effect of the drug's action by decreasing renal clearance
bacitracin, when combined with acyclovir, is serious and risky, leading to nephrotoxicity
an increase in the severity of nephrotoxicity can be seen if acyclovir is taken with bumadizone
the rate of excretion of aurothioglucose may be reduced with acyclovir
both amikacin and acyclovir exacerbate ototoxicity and/or nephrotoxicity
acyclovir + amoxicillin
either raises the other's levels by lowering renal clearance
both cisplatin and acyclovir exacerbate ototoxicity and/or nephrotoxicity
by reducing renal clearance, acyclovir raises peramivir levels
both tobramycin and acyclovir cause increased ototoxicity and/or nephrotoxicity
the excretion of taurocholic acid may diminish when combined with acyclovir
may have a decrease in excretion when combined with acyclovir
the risk of nephrotoxicity may be increased
the risk of nephrotoxicity may be increased
neomycin PO and acyclovir both cause increased ototoxicity and/or nephrotoxicity
the risk of nephrotoxicity may be increased
the risk of nephrotoxicity may be increased
the rate of metabolism of zotepine may be reduced with acyclovir
when combined with acyclovir, metabolism of bufylline may be reduced
caffeic acid when combined with acyclovir results in more adverse effects
acyclovir might lead to a reduction in the rate of excretion of telavancin, potentially leading to elevated levels of serum
the activity of the anthrax vaccine can be reduced when used in combination with acyclovir
Increased serum concentration resulted from decreased renal clearance.
when both drugs are combined, there may be an increased effect of acyclovir by acidic (anionic) drug competition for renal tubular clearance 
Viruses seize to control of living cells by exploiting them for their own reproduction which is often at detriment of the host cell. Acyclovir undergoes activation by the virus itself, where virus utilizes activated form of acyclovir instead of usual nucleoside employed in DNA synthesis which plays a pivotal process in viral replication. The integration of active acyclovir into newly forming viral DNA disrupts synthesis of DNA by impeding the production of virus. Infected cells demonstrate a increased absorption of acyclovir compared to normal cells and an increased conversion to its active form thereby extending its antiviral effectiveness.
Frequency defined
>10% (oral)
Malaise (<12%)
1-10% (Parenteral)
Nausea (7%)
Rash or hives (2%)
Elevated transaminase levels (1-2%)
Inflammation or phlebitis at injection site (9%)
Vomiting (7%)
1-10% (oral)
Headache (2%)
Nausea (2-5%)
Diarrhea (2-3%)
Vomiting (<3%)
<1%
Fatigue
Angioedema
Abdominal pain
Alopecia
Ataxia
Anaphylaxis
Aggression/confusion
Coma
Dizziness
Anorexia
Disseminated intravascular coagulation (DIC)
Anemia
Agitation
None
Contraindications
Cautions
Breastfeeding
Pregnancy consideration:
No data is available regarding administration of the drug during pregnancy.
Breastfeeding warnings:
No data is available regarding excretion of drug in breast milk.
Pregnancy category:
Category A:Â well-controlled and satisfactory studies show no risk to the fetus in first or later trimester.
Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women.
Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.
Category D:Â adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.
Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.
Category N: No data is available for the drug under this category.
Pharmacology:
Acyclovir is a synthetic nucleoside, that prevents many herpesviruses from replicating their DNA and from acting as viral DNA polymerase.
Pharmacodynamics:
Acyclovir converts to acyclovir monophosphate by thymidine kinase action. Subsequently, guanylate kinase converts acyclovir monophosphate to diphosphate form. The acyclovir triphosphate forms by converting acyclovir diphosphate by succinyl-CoA synthetase, pyruvate kinase, creatine kinase, nucleoside diphosphate kinase, phosphoglycerate kinase, adenylosuccinate synthetase, and phosphoenolpyruvate carboxykinase. Acyclovir triphosphate exhibits a greater affinity for DNA polymerase, viral DNA compared to DNA polymerase, which is cellular that leading to its DNA incorporation. The DNA chain termination occurs because of the absence of 2′ C and 3′ C. In certain instances, forceful competition by acyclovir triphosphate for DNA polymerase (viral) prevents other bases from enzyme association and rendering it inactive.
Pharmacokinetics:
Bioavailability is 15-30 % (PO)
The time to achieve peak effect is 1 hour (IV) and 1.5-2 hours (PO)
Protein-bound is 9-33 %
Volume of distribution of betrixaban is 0.8 L/kg
The half-life is 4 hours (Neonates), 3hr (adults), and 2-3 hours (1-12 years of age).
Unchanged drug is excreted 62-90% in urine.
This drug is intended for intravenous infusion, only with caution against rapid infusion. It should be administered over 1 hour at a consistent rate to prevent renal damage. Store at room temperature, reconstitute for injection and use within 24 hours.
Generic Name: acyclovir
Pronounced: uh-SY-kloh-veer
Why do we use acyclovir?
Acyclovir prevents discomfort and involves in healing process of blisters or sores in individuals affected with herpes zoster, varicella, and initial/recurrent episodes of genital herpes. It belongs to the analogue which is a synthetic nucleoside, which functions by impeding the proliferation of herpes virus within the body. It is important to note that it may not prevent the transmission of virus to others or does not cure genital herpes.
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