Drug Nutrient Depletion Guide

Antibiotics (Broad-Spectrum): What It Depletes and How to Replenish

Antibiotics (Broad-Spectrum) (Amoxicillin, Cipro, Doxycycline, Azithromycin) is associated with clinically documented depletion of 3 key nutrients. Below you'll find the mechanism, clinical evidence, and evidence-based replenishment protocols for each.

This page is educational content based on published clinical trials. All supplement recommendations should be discussed with your prescribing physician before implementation. Evidence ratings follow the same RCT-first methodology used across the full Evidence Based Longevity database.
3 Documented Depletions · RCT Evidence
1
Probiotics / Gut Microbiome
Critical Depletion Risk
How It Depletes

Broad-spectrum antibiotics eliminate both pathogenic AND beneficial bacteria. A single course can reduce gut microbiome diversity by 30–50%, with some species not recovering for 6+ months.

Clinical Evidence

Dethlefsen & Relman (2011) Science — antibiotic-induced microbiome disruption with lasting effects

Symptoms of Deficiency

Diarrhea, bloating, increased infection susceptibility, immune dysregulation, C. diff risk

Evidence-Based Replenishment

Multi-strain probiotic (10–50 billion CFU) during and 2 weeks after antibiotics. Take 2 hours apart from antibiotic dose. Saccharomyces boulardii specifically reduces C. diff risk.

View on Fullscript: Jarrow Saccharomyces Boulardii + Thorne FloraSport

Discuss with your physician before adjusting supplementation. This is educational content, not medical advice.

2
Vitamin K2
Moderate Depletion Risk
How It Depletes

Gut bacteria are a significant source of Vitamin K2 (menaquinones). Antibiotic courses reduce K2 production. Relevant especially for those on warfarin.

Clinical Evidence

Conly & Stein (1992) — reduced menaquinone production with antibiotic use

Symptoms of Deficiency

Impaired arterial calcium regulation, bone health impairment

Evidence-Based Replenishment

Vitamin K2 (MK-7) 100mcg daily after antibiotic course.

View on Fullscript: Thorne Vitamin D/K2 Liquid

Discuss with your physician before adjusting supplementation. This is educational content, not medical advice.

3
B Vitamins (Biotin, B complex)
Moderate Depletion Risk
How It Depletes

Gut bacteria produce several B vitamins (B7/biotin, B12, K). Antibiotic eradication reduces this endogenous production.

Clinical Evidence

Said (2011) — bacterial B vitamin synthesis reduced by gut microbiome disruption

Symptoms of Deficiency

Fatigue, hair loss (biotin), neurological symptoms

Evidence-Based Replenishment

B-complex supplement during and 2 weeks after antibiotic course.

View on Fullscript: Thorne Basic B Complex

Discuss with your physician before adjusting supplementation. This is educational content, not medical advice.

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