Antibiotics
changed
medicine.
They also
change
your gut.
A clinically-studied postbiotic — the rationally-designed way to protect and restore your gut during and after antibiotics and the stressors of modern life.
What throws your gut off balance.
Antibiotics, stress, diet, medications, travel — everyday life takes a toll on your gut microbiome.
Antibiotics
Wipe out the good bacteria along with the bad — and repeated courses are linked to a higher risk of inflammatory bowel disease (IBD).
Stress
Triggers inflammation and disrupts the gut–brain axis.
Bad Diet & GLP-1s
Slow digestion and cut essential nutrient absorption.
Processed food & alcohol
Feed the wrong microbes and thin your diversity.
Sugar
Excess sugar takes a toll on your gut and feeds the wrong microbes.
Long-haul flights & sleep
Time-zone shifts and lost sleep disrupt gut rhythms and your immune barrier.
Pesticides
Residues on everyday produce can alter the balance of gut bacteria.
Everyday medications
NSAIDs, PPIs, hormone therapy and birth control, SSRIs and antidepressants all chip away at gut balance.
When your gut is off, you feel it everywhere.
Your gut does far more than digest. A disrupted microbiome ripples through your whole body.
Digestion
Bloating, irregularity, and everyday discomfort.
Immunity
Around 70% of your immune system lives in your gut.
Mood & focus
Your gut makes serotonin, GABA, and dopamine — roughly 90% of the body's serotonin is produced there, not in the brain.
Hormones
Gut microbes help regulate the hormones that keep you in balance.
Metabolism & weight
Your microbiome influences how you store energy and manage weight.
Blood sugar
Gut balance plays a role in how your body handles glucose.
Anxiety & depression
Microbiome signals reach the brain and can shape how you feel.
Energy
Weak absorption leaves you running on empty.
Inflammation
Imbalance can drive system-wide inflammation.
Nutrient absorption
A disrupted gut pulls less goodness from your food.
We didn't just say it. We studied it.
dr mac's is a clinically-studied postbiotic — made to protect and restore your gut when antibiotics and modern life throw it off balance.
40% more gut diversity preserved.
vs. placebo in a randomized, placebo-controlled trial of Gut Support taken during antibiotics.
Read the RCT in Infection & Immunity (ASM) →Doctor-designed, doctor-recommended.
Created by a team of microbiome scientists and practicing clinicians — real people who wanted a gut product that actually works.
Why a postbiotic is the right tool for the antibiotic window.
A better fit for the moment your gut is under attack.
Probiotic — live bacteria
- ✕Live cells vulnerable to the antibiotic mid-course
- ✕Must colonize the gut — and is often resisted
- ✕Can delay native microbiome recovery in studies
- ✕Rare bloodstream-infection concern in the immunocompromised
Postbiotic — metabolites & components
- ✓No live cells for the antibiotic to kill — works mid-course
- ✓No colonization needed — delivers the end-product directly
- ✓Supports recovery without impeding recolonization
- ✓No live organisms = lower infection-risk profile; shelf-stable
“Antibiotics damage the gut and its resident flora. Preventing that damage can make a real difference to overall health.”— From the microbiome research community
The clinically-studied postbiotic for the antibiotic moment.
Gut Support
Support your gut balance during and after antibiotics. Postbiotic Nutrients · Microbiome 2.0.
Gut Support Gummies
Support your gut balance during and after antibiotics. Postbiotic Nutrients · Microbiome 2.0.
One adjunct for every modern stressor.
Modern life impacts your gut in ways most people don't see. Each SKU is designed to protect and replenish for a specific moment.
Antibiotic & Stress
Support your gut balance during and after antibiotics.
GLP-1 Companion
Digestive comfort and gut balance for those on GLP-1s.
Meet MACs — and Dr. Mac.
What are MACs?
MACs — microbiota-accessible carbohydrates — are the specific dietary plant fibers that feed the beneficial bacteria in your gut. Defined by Stanford Medicine researchers Dr. Erica Sonnenburg and Dr. Justin Sonnenburg, MACs are the fuel a healthy microbiome runs on.
The catch: low-MAC Western diets starve these microbes — thinning gut diversity in a way that can compound across generations.
Dr. Mac, our Chief Medical Officer.
It's no accident we're dr mac's. Dr. Mac — our Chief Medical Officer — gave the brand its name, and MACs sit at the very heart of the science we're built on.
Find dr mac's on the retail shelf.
A patient, a physician, and a cancer-research team saw the same problem.
dr mac's was built to fix it — a postbiotic that protects the gut during antibiotics, then proven in real patients. Postbiotic Nutrients · Microbiome 2.0, from PBP Consumer Health.