About PB8

PB8 makes multi-strain probiotic dietary supplements, and has kept the same idea on the shelf since 1989: more than one strain in a capsule, and a label that tells you which.

What PB8 is

PB8 started with one formula, and it is still the one most people know: eight strains of Lactobacillus and Bifidobacterium in a serving of two capsules, with inulin from chicory root. For 37 years that bottle has been on US shelves, for many of them under the words "Pro-Biotic Acidophilus", today as PB8 Original. The name on the older bottles tells you where it comes from: Nutrition Now, Inc.

What has stayed the same is the habit of naming every strain. Each of our labels lists the strains in its blend by genus, species and strain code, so you can read exactly what you are taking and compare it with any other probiotic on the shelf.

Six formulas

The classic line is three formulas in classic capsules: the Original, the Vegetarian (the same blend in a capsule of plant cellulose and water) and Immune Support, one capsule a day with 15 billion CFU and more than ten strains, made to help support the immune system as well as digestion.*

The 3-in-1 line is three formulas in delayed release capsules, each with prebiotic fiber, probiotic cultures and postbiotics on the label: the Synbiotic 3-1 with 65 billion CFU and 31 strains, the Women's Probiotic with 50 billion CFU and 27 strains, and the Vaginal Probiotic with 21 strains led by Lactobacillus reuteri RC-14 and Lactobacillus rhamnosus GR-1.

Who it is for

Adults. The classic formulas are for any adult who wants a daily probiotic, and the Women's and Vaginal formulas are for women 18 and over. Every label asks you to talk with your doctor first if you are pregnant or nursing, take medication or have a medical condition, and we would say the same: a pharmacist can look at the label with you and tell you whether it fits the rest of what you take.

None of our formulas is a medicine. They are dietary supplements made to support what each label says, and each label carries the FDA statement that the claim has not been evaluated by the agency.*

How we write these pages

Every Supplement Facts table on this site is typed from the label of its formula, line for line, in the order the label prints it. The price per day you see on each card is the price of that bottle divided by the days it lasts at the label serving. The prices themselves come from our scheduled catalog update, and how we update them is a page of its own.

This page is general product information, not medical advice. Read the label of the product you use, and ask your doctor or pharmacist before you start a supplement if you have a medical condition, take medication, or are pregnant or nursing.

What the public sources say

FDA: Structure/Function Claims. Structure/function claims on dietary supplements are not pre-approved by the FDA; the manufacturer must have substantiation that the claim is truthful and not misleading, and the label must carry a disclaimer that the FDA has not evaluated the claim and that the product is not intended to diagnose, treat, cure or prevent any disease. Read October 25, 2026.
NCCIH: Probiotics, Usefulness and Safety. Probiotics are live microorganisms intended to have health benefits; the most common belong to the groups Lactobacillus and Bifidobacterium, and different types may have different effects, so what one kind of Lactobacillus does cannot be assumed of another. Probiotics have an extensive history of apparently safe use, particularly in healthy people, while the risk of harmful effects is greater in people with severe illnesses or compromised immune systems. Synbiotics are products that combine probiotics and prebiotics, and supplement labels may make structure/function claims without FDA approval but not disease claims. Read October 25, 2026.

Questions

Questions about PB8

What is PB8?

PB8 is a line of multi-strain probiotic dietary supplements on US shelves since 1989: six formulas, from the eight-strain Original to the 65-billion Synbiotic 3-1.

Who makes PB8?

PB8 comes from Nutrition Now, Inc., whose name is on our older bottles. The strain names on our labels are trademarks of the companies that own them, named on each label.