Lactobacillus Acidophilus

Background

Lactobacilli are bacteria that normally live in the human small intestine and vagina. Lactobacillus acidophilus is generally considered to be beneficial because it produces vitamin K, lactase, and anti-microbial substances such as acidolin, acidolphilin, lactocidin, and bacteriocin. Multiple human trials report benefits of L. acidophilus for bacterial vaginosis. Other medicinal uses of L. acidophilus are not sufficiently studied to form clear conclusions.

The term "probiotic" is used to describe organisms that are used medicinally, including bacteria such as L. acidophilus and yeast such as Saccharomyces boulardii .

Although generally believed to be safe with few side effects, oral L. acidophilus should be avoided in people with intestinal damage, a weakened immune system, or with overgrowth of intestinal bacteria.

Synonyms

Acidophilus, Acidophilus Extra Strength®, acidophilus milk, Actimel®, Bacid®, Cultura®, DDS-Acidophilus, Endolac®, Enpac®, Fermalac® (Canadian), Florajen®, fresh poi, Gynoflor®, Infloran®, Kala®, Kyo-Dophilus®, L-92, L. acidophilus, L. acidophilus OLL2769, L. acidophilus milk, L. acidophilus yogurt, Lacteol Fort®, lactic acid-producing bacteria (LAB), Lactinex®, Lactobacillaceae (family), lactobacilli, lactobacillus, Lactobacillus acidophilus 145 , Lactobacillus acidophilus DDS-1, Lactobacillus acidophilus LA 02, Lactobacillus acidophilus La5, Lactobacillus acidophilus L-92, Lactobacillus acidophilus NCFM, Lactobacillus acidophilus NCK56, Lactobacillus acidophilus strain 27L, Lactobacillus acidophilus strain LB (LaLB), Lacto Bacillus, MoreDophilus?®, Narine®, poi, Probiata®, Pro-Bionate®, probiotic, sour poi, Superdophilus®, yogurt.

Evidence

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Uses based on scientific evidence	Grade^*
Bacterial vaginosis Multiple human studies report that Lactobacillus acidophilus vaginal suppositories are effective in the treatment of bacterial vaginosis. A small number of studies suggest that eating yogurt enriched with Lactobacillus acidophilus may be similarly beneficial. Additional research is necessary before a firm conclusion can be reached. Patients with persistent vaginal discomfort are advised to seek medical attention.	B
Allergy treatment (Japanese cedar pollen) A small study was conducted to evaluate the effects of Lactobacillus acidophilus strain L-92 (L-92) on the symptoms of Japanese cedar-pollen allergy with positive results. Further research is needed before a decision can be made.	C
Asthma There is limited research in this area, with unclear results.	C
Diarrhea prevention A small amount of human research suggests that Lactobacillus acidophilus may not be effective when used to prevent diarrhea in travelers or in people taking antibiotics. Several studies report that the related species Lactobacillus GG may be helpful for the prevention of diarrhea in children and travelers. Additional study is needed in these areas before a firm conclusion can be drawn.	C
Diarrhea treatment (children) A small amount of research in children, using different forms of acidophilus, reports no improvement in diarrhea. Future studies should use a viable Lactobacillus acidophilus culture to assess effects on diarrhea. Lactobacillus GG, a different species, is suggested by multiple human studies to be a safe and effective treatment for diarrhea in otherwise healthy infants and children. Lactobacillus acidophilus may aid in the management of chronic or persistent diarrhea and bacterial-overgrowth related diarrhea. Further research is needed to determine what dose may be safe and effective.	C
Hepatic encephalopathy (confused thinking due to liver disorders) There is limited study in this area, with mixed results.	C
High cholesterol There is conflicting information from several human studies regarding the effects of Lactobacillus acidophilus- enriched dairy products on lowering blood levels of total cholesterol or low-density lipoprotein ("bad cholesterol").	C
Irritable bowel syndrome Human studies report mixed results in the improvement of bowel symptoms after taking Lactobacillus acidophilus by mouth.	C
Lactose intolerance There is conflicting information from several human studies as to whether using Lactobacillus acidophilus by mouth improves digestion of lactose. More research is needed in this area a before a conclusion can be drawn.	C
Necrotizing enterocolitis prevention in infants One human study using L. acidophilus in combination with another bacterium ( B. infantis ) in infants reported fewer cases of necrotizing enterocolitis (severe inflammation of the gut), and no complications related to treatment. Additional research is necessary in this area before a conclusion can be drawn.	C
Vaginal candidiasis (yeast infection) Lactobacillus acidophilus taken by mouth or as a vaginal suppository has not been adequately assessed for the prevention or treatment of vaginal yeast infections. More research is needed in this area a before a conclusion can be drawn.	C

*Key to grades

A: Strong scientific evidence for this use;

B: Good scientific evidence for this use;

C: Unclear scientific evidence for this use;

D: Fair scientific evidence against this use;

F: Strong scientific evidence against this use.

Grading rationale

Uses based on tradition or theory

The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Acne, AIDS, cancer, canker sores, colitis, colon cancer prevention, constipation, diaper rash, Crohn's disease, diverticulitis,E. coliinfection in cancer patients, fever blisters, heart disease, heartburn, hives, immune enhancer, indigestion, infection, overgrowth of bacteria in the small bowel, preoperative prevention of infections or gut bacteria loss, stomach ulcer, thrush, ulcerative colitis, urinary tract infection.

Dosing

The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.

Adults (18 years and older)

Tablets/capsules/liquid/yogurt: Expert opinion suggests that a dose between 1 and 10 billion viable (live) L. acidophilus bacteria taken daily in divided doses is sufficient for most people. Higher doses may cause mild abdominal discomfort, and smaller doses may not be able to establish a stable population in the gut. For vaginal bacterial infections, a dose that has been used is 8 ounces of yogurt containing L. acidophilus in a concentration of 100 million colony-forming units (108 CFU) in each milliliter. Capsules containing 1.5 grams of Lactobacillus acidophilus were used in one study.

Vaginal suppository: Doses that have been used for vaginal infections include 1 to 2 tablets (containing 10 million to 1 billion CFU in each tablet), inserted into the vagina once or twice daily.

Anal suppository: Capsules containing 1.5 grams of Lactobacillus acidophilus have been used to treat diarrhea.

Children (younger than 18 years)

Tablets/capsules/liquid: Some natural medicine textbooks and experts suggest that one-quarter teaspoon or one-quarter capsule of commercially available L. acidophilus may be safe for use in children for the replacement of gut bacteria destroyed by antibiotics. Up to 12 billion lyophilized heat-killed L. acidophilus has been given every 12 hours for up to five days. It is often recommended that L. acidophilus supplements be taken two hours after antibiotic doses, because antibiotics may kill L. acidophilus if taken at the same time. Consult a qualified healthcare practitioner prior to using L. acidophilus in children, and use cautiously in those under three years of age.

Applied to the skin: Liquid preparations have been used on the diaper area to treat yeast infections, although safety and effectiveness are not well studied. Consult a qualified healthcare practitioner prior to using L. acidophilus in children, and use cautiously in those under three years of age.

Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Allergies

Lactose sensitive people may develop abdominal discomfort from dairy products containing L. acidophilus.