85/100 · Critical
Manufactured by ViiV Healthcare Company
High Safety Concerns with Lamivudine, Particularly in Pregnancy and Hepatic Function
57,073 FDA adverse event reports analyzed
Last updated: 2026-05-12
LAMIVUDINE is a medication tracked in the FDA Adverse Event Reporting System (FAERS), manufactured by ViiV Healthcare Company. Based on analysis of 57,073 FDA adverse event reports, LAMIVUDINE has a safety score of 85 out of 100. This score indicates a relatively favorable safety profile, with fewer or less severe adverse events compared to many other tracked medications. The most commonly reported adverse reactions for LAMIVUDINE include FOETAL EXPOSURE DURING PREGNANCY, VIROLOGIC FAILURE, DRUG RESISTANCE, DRUG INTERACTION, PATHOGEN RESISTANCE. This page provides a comprehensive breakdown of reported side effects, safety signals, patient demographics, and AI-powered safety analysis for LAMIVUDINE.
Lamivudine has a safety concern score of 85 out of 100, placing it in the high concern category based on analysis of FDA adverse event data. The FDA has received approximately 57,073 adverse event reports for this medication, which is primarily manufactured by Viiv Healthcare Company.
The most commonly reported adverse events include Foetal Exposure During Pregnancy, Virologic Failure, Drug Resistance. Of classified reports, 96.1% were designated as serious by the FDA, meaning they involved hospitalization, disability, or other significant medical outcomes. Serious adverse events, especially related to fetal exposure and renal failure, are common.
Hepatic function abnormalities and increased viral load are significant safety concerns. Drug interactions and resistance are frequent, requiring careful monitoring.
Patients taking Lamivudine should monitor for the commonly reported side effects and contact their healthcare provider if they experience any unusual symptoms. Lamivudine can cause drug interactions and resistance, necessitating careful monitoring and dose adjustments. This analysis is based on voluntary FDA adverse event reports and should not replace professional medical advice.
Lamivudine received a safety concern score of 85/100 (high concern). This is based on a 96.1% serious event ratio across 30,416 classified reports. The score accounts for 57,073 total adverse event reports and 100 distinct reaction types. This high score reflects a significant proportion of serious adverse events in the reporting data.
Adverse event reports by sex: Male: 14,454, Female: 8,288, Unknown: 183. The most frequently reported age groups are age 54 (1,013 reports), age 52 (590 reports), age 50 (492 reports). These demographics reflect reporting patterns and may not represent the full patient population.
Out of 30,416 classified reports for LAMIVUDINE:
The FDA classifies an adverse event as “serious” if it results in death, hospitalization, disability, congenital anomaly, or requires intervention to prevent permanent damage.
Demographics reflect voluntary FDA adverse event reporting patterns and may not represent the full patient population.
Lamivudine can cause drug interactions and resistance, necessitating careful monitoring and dose adjustments.
If you are taking Lamivudine, here are important things to know. The most commonly reported side effects include foetal exposure during pregnancy, virologic failure, drug resistance, drug interaction, pathogen resistance. While many of these may be mild and temporary, you should contact your healthcare provider if any symptoms are severe or persistent. Monitor liver function and viral load regularly, especially in patients with pre-existing liver conditions. Use caution in pregnant women, as fetal exposure can lead to serious complications. If you experience a serious adverse reaction, seek emergency medical attention immediately or call 911. You can report side effects to the FDA's MedWatch program at 1-800-FDA-1088.
Regulatory oversight is ongoing, with updates to warnings and safety information based on new data.
The FDA has received approximately 57,073 adverse event reports associated with Lamivudine. These reports come from healthcare professionals, consumers, and manufacturers through the FDA Adverse Event Reporting System (FAERS). Note that the number of reports does not directly indicate the frequency of side effects, as adverse events are voluntarily reported and may be underrepresented.
The most frequently reported adverse events for Lamivudine include Foetal Exposure During Pregnancy, Virologic Failure, Drug Resistance, Drug Interaction, Pathogen Resistance. By volume, the top reported reactions are: Foetal Exposure During Pregnancy (2,012 reports), Virologic Failure (1,948 reports), Drug Resistance (1,941 reports). These figures reflect FDA adverse event reports and may not represent the true incidence rate of these side effects in all patients taking Lamivudine.
Out of 30,416 classified reports, 29,224 (96.1%) were classified as serious and 1,192 as non-serious. The FDA classifies an event as "serious" if it results in death, hospitalization, disability, or other medically significant outcomes. A higher serious-event ratio warrants closer attention but does not necessarily mean the drug is unsafe.
Adverse event reports for Lamivudine break down by patient sex as follows: Male: 14,454, Female: 8,288, Unknown: 183. This distribution reflects reporting patterns rather than actual risk differences between groups. Reporting rates can be influenced by prescribing patterns, disease demographics, and reporting behavior.
The most frequently reported age groups for Lamivudine adverse events are: age 54: 1,013 reports, age 52: 590 reports, age 50: 492 reports, age 40: 464 reports, age 45: 429 reports. Age-related reporting patterns can reflect both the demographics of the patient population and potential age-related susceptibility to certain side effects.
The primary manufacturer associated with Lamivudine adverse event reports is Viiv Healthcare Company. Multiple manufacturers may produce generic versions of this drug. The manufacturer listed reflects the most frequently reported brand in FDA adverse event data.
Beyond the most common reactions, other reported adverse events for Lamivudine include: Viral Mutation Identified, Depression, Pyrexia, Drug Ineffective, Anaemia. Less common side effects can still be clinically significant. Patients should report any unusual symptoms to their healthcare provider.
You can report adverse events from Lamivudine to the FDA through their MedWatch program at www.fda.gov/medwatch, by calling 1-800-FDA-1088, or by completing Form FDA 3500. Healthcare professionals, consumers, and manufacturers can all submit reports. Reporting helps the FDA monitor drug safety after approval.
Lamivudine has a safety concern score of 85 out of 100 (high concern). This score is calculated from the ratio of serious to non-serious adverse events, the diversity of reported reactions, and the overall volume of reports relative to usage. Serious adverse events, especially related to fetal exposure and renal failure, are common.
Key safety signals identified in Lamivudine's adverse event data include: Fetal exposure and pregnancy complications are among the most reported serious adverse events.. Hepatic failure and enzyme increases are critical safety signals.. Drug resistance and virologic failure are major concerns in treatment efficacy.. These signals are derived from patterns in FDA reports and should be discussed with a healthcare provider for personalized assessment.
Lamivudine can cause drug interactions and resistance, necessitating careful monitoring and dose adjustments. Always inform your healthcare provider about all medications, supplements, and over-the-counter drugs you are taking before starting Lamivudine.
Monitor liver function and viral load regularly, especially in patients with pre-existing liver conditions. Use caution in pregnant women, as fetal exposure can lead to serious complications.
Lamivudine has 57,073 adverse event reports on file with the FDA. Hepatic function abnormalities and increased viral load are significant safety concerns. The volume of reports for Lamivudine reflects both the drug's usage level and the vigilance of the reporting community.
Regulatory oversight is ongoing, with updates to warnings and safety information based on new data. For the most current regulatory information, check the FDA's drug labeling database or consult your pharmacist.
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