Partial
Mostly Aligned
Patient Risk:
Low
Summary
Partial alignment. The label contains limited supported elements (notably renal-dose adjustment guidance and a probenecid interaction note under dosage/administration), but the extracted claims assert multiple antibiotic-interaction statements that are not supported by the provided prescribing information and include numerous unverified anecdotes.
Category Scores
Accurate Statements
Space doses if using probenecid (rarely with antibiotics) as it slows acyclovir clearance.
Explicitly stated in DOSAGE AND ADMINISTRATION.
Acyclovir requires dose adjustment in renal impairment.
Label indicates that dosage adjustment is recommended for renal impairment (see DOSAGE AND ADMINISTRATION).
Unsupported Statements
Acyclovir shows no major drug interactions with most antibiotics.
Label provides no such general statement; no supporting interaction data for 'most antibiotics'.
Acyclovir shows no unique side effects when combined with most antibiotics.
No such assertion in label; no comprehensive interaction safety profile with antibiotics.
There are no clinically significant interactions between acyclovir and common antibiotics such as amoxicillin, ciprofloxacin, or doxycycline.
Label does not provide evidence for these specific antibiotic interactions.
Side effects from the combination mirror those of antibiotics (nausea, diarrhea, or rash).
Label does not describe antibiotic-mirroring adverse effects for antibiotic–acyclovir combinations.
Side effects from the combination mirror those of acyclovir (headache or dizziness).
Label does not describe combination-specific adverse effects mirroring acyclovir.
Side effects from the combination are not amplified compared with taking each drug alone.
Label provides no evidence on amplification of adverse effects in combinations.
No interaction between acyclovir and penicillins (e.g., amoxicillin).
Label does not substantiate a lack of interactions with penicillins.
Both acyclovir and penicillins are cleared by the kidneys without competition.
Label does not provide data on renal clearance competition between acyclovir and penicillins.
There is a theoretical risk of additive kidney strain in dehydrated patients or those with poor renal function when combining acyclovir with fluoroquinolones, potentially worsening acyclovir's rare nephrotoxicity (crystal formation in urine).
Label contains no interaction data specific to fluoroquinolones and acyclovir nephrotoxicity.
Hydration mitigates the theoretical risk of kidney strain with fluoroquinolones.
Label does not discuss hydration effects on fluoroquinolone–acyclovir interactions.
No issues reported with macrolides (e.g., azithromycin).
Label contains no explicit statements regarding macrolide interactions.
Doxycycline: Safe together; no pharmacokinetic changes.
Label provides no confirmation of this claim.
Rare case reports note heightened gastrointestinal upset with the acyclovir-tetracycline combination.
Label contains no such anecdotal evidence; no tetracycline combination data.
Rare case reports note allergic reactions with the acyclovir-tetracycline combination.
Label contains no such anecdotal evidence; no tetracycline combination data.
Some antibiotics like vancomycin or aminoglycosides (gentamicin) also stress kidneys.
Label discusses renal considerations but does not specifically state these antibiotics with acyclovir in this context.
Co-use can elevate creatinine levels additively, risking acute kidney injury in vulnerable patients (elderly, dehydrated).
Label provides no quantified additive creatinine risk data for these combinations.
Labs show this in <1% of cases.
Label does not provide such laboratory incidence data for interactions.
Symptoms include reduced urine output or fatigue.
Label lists renal impairment concerns but does not present these symptoms as a consequence of antibiotic–acyclovir combinations specifically.
Online forums mention amplified nausea, fatigue, or metallic taste with acyclovir plus antibiotics like cephalexin.
Label contains no forum-derived anecdotal data.
These reports are anecdotal and unverified.
Label does not discuss such anecdotes.
No large-scale data confirms causation over coincidence.
Label does not provide causation data for antibiotic–acyclovir interactions.
Avoid in severe renal failure without specialist oversight.
Label does not use this exact phrasing; it discusses dose adjustment for renal impairment rather than universal avoidance.
Space doses if using probenecid (rarely with antibiotics) as it slows acyclovir clearance.
This is the only fully supported administration-related claim; other statements about interactions with probenecid are not addressed in the remaining claims.
Always check for allergies first.
Label does not state this as a formal instruction; allergy considerations are not presented in these sections.
Contradictions
Important Omissions
Key label warnings about renal failure, TTP/HUS, and immunocompromised patient risks are not addressed in the claims.
Importance:
Moderate
No explicit mention of the label's drug interaction details or lack thereof with specific antibiotic classes beyond the general drug interactions section.
Importance:
Moderate
Safety Assessment
Potential Patient Risk:
Low
Label indicates renal-dose adjustments and hydration considerations; no demonstrated clinically significant antibiotic interactions were described in the provided sections. However, there are known renal safety concerns requiring precautions in impairment.
Regulatory Assessment
| On Label |
Yes |
| Off-label Discussion |
No |
| Promotes Unapproved Use |
No |
| Hallucination Risk |
Low |
Recommendation
Mostly Aligned
Primary Issue
Significant gaps in claiming no antibiotic interactions and in summarizing safety warnings present in the label; add supported statements only and address renal-related warnings (TTP/HUS, renal impairment) from the label.
Suggested Improvement
Limit claims to those supported by the label (renal-dose adjustment, hydration guidance, and specific administration notes like probenecid interaction). Remove or rephrase unsupported antibiotic-interaction claims; incorporate explicit warnings from WARNINGS: renal complications and TTP/HUS; align with the label's Drug Interactions section.