Usage
Lactobacillus refers to a genus of gram-positive, facultative anaerobic or microaerophilic, rod-shaped, non-spore-forming bacteria. They are a major part of the lactic acid bacteria group (i.e., bacteria that convert sugars to lactic acid). These probiotics are used for a variety of conditions related to the gut, including diarrhea, vaginal infections, and irritable bowel syndrome, to restore healthy gut flora after antibiotic use and to prevent antibiotic-associated or Clostridioides difficile diarrhea. While often added to fermented foods like yogurt, they are more commonly found in dietary supplements. They do not fit neatly into a single pharmacological classification but can be considered as probiotic agents, or biological agents when administered for specific conditions. The mechanism of action differs between species and applications, but generally, Lactobacillus species function by competing with pathogenic bacteria for resources, producing lactic acid and antimicrobial substances, and modulating the immune system.
Alternate Names
Lactobacillus is the scientific and generic name for the genus. It is sometimes referred to as lactic acid bacteria or LAB, although this term is not specific to Lactobacillus and encompasses a wider range of bacteria. Various species exist, including Lactobacillus acidophilus, Lactobacillus rhamnosus GG, Lactobacillus reuteri, Lactobacillus casei, and others. Brand names for Lactobacillus-containing products vary widely depending on the specific strains and formulation, with some popular brands including Culturelle, Bacid, and numerous others. Many products combine several Lactobacillus species or include other probiotics.
How It Works
Pharmacodynamics
Lactobacillus species exert their effects by altering the gut microbiome, competing with pathogens, and influencing the host’s immune response. They produce lactic acid, lowering the pH of the gut, which inhibits the growth of several harmful bacteria. Certain species generate antimicrobial substances like bacteriocins which directly target pathogens. They also enhance the intestinal barrier function, reducing gut permeability and preventing pathogens and toxins from crossing into the bloodstream. Some species modulate the immune system by interacting with intestinal epithelial cells and immune cells such as dendritic cells and lymphocytes.
Pharmacokinetics
Lactobacillus species are primarily taken orally, either in food or as supplements. They are not absorbed systemically in significant amounts but reside within the gastrointestinal tract where they exert their beneficial effects. The viability of Lactobacillus strains is crucial for their effectiveness. Thus, storage and administration instructions must be carefully followed to prevent bacterial death before reaching the target site. Elimination occurs through excretion in feces. They are not metabolized by liver enzymes or excreted by the kidneys in significant quantities.
Dosage
Dosage recommendations for Lactobacillus vary according to the specific strain, formulation, and health condition being addressed. No standardized dosage regimen exists across all applications, and colony forming units (CFUs) are typically used to quantify the number of viable bacteria in a dose.
Standard Dosage
Adults:
For general gut health maintenance: 1 to 15 billion CFUs daily.
For prevention or treatment of diarrhea: 1 to 2 billion CFUs daily, though some physicians recommend up to 10 to 15 billion CFUs daily.
For antibiotic-associated diarrhea: 10-20 billion CFUs of L. rhamnosus GG, taken once or twice daily during the antibiotic course and continued for one week afterward.
For vaginal infections: 1 to 50 billion CFUs of specific strains, sometimes administered vaginally.
As with all medications, it is important to consult with a healthcare professional for individualized recommendations.
Children:
Pediatric dosages are not always specified. It is advisable to start with a lower dose than that recommended for adults and gradually increase it as tolerated. A general guideline is to use one-quarter of the adult dosage for children under 6 years, half for children 6 to 12 years, and the full adult dose for adolescents. Use in newborns and infants should be under a pediatrician’s supervision.
Special Cases:
Elderly Patients: No specific adjustments.
Patients with Renal Impairment: No specific adjustments.
Patients with Hepatic Dysfunction: No specific adjustments.
Patients with Comorbid Conditions: No specific adjustments.
However, in all cases, consult with a healthcare professional.
Clinical Use Cases
Lactobacillus has not been approved for use in specific medical settings like intubation, surgical procedures, mechanical ventilation, ICU use, or emergency situations. It primarily functions as a dietary supplement for gut health. While it might be used concurrently with standard medical treatment in certain conditions, it is not considered a drug intervention. Further research is needed to determine its potential role in clinical use cases.
Dosage Adjustments
No specific dosage adjustments are needed for renal/hepatic dysfunction, metabolic disorders, or genetic polymorphisms. However, patients with weakened immune systems should use probiotics with caution.
Side Effects
Common Side Effects
Generally well-tolerated. Mild and transient bloating, gas, and sometimes diarrhea can occur, especially when starting treatment.
Rare but Serious Side Effects
In rare cases, individuals with severely compromised immune systems may experience systemic infections.
Long-Term Effects
No significant long-term effects are documented when used as directed.
Adverse Drug Reactions (ADR)
Rare cases of bacteremia and fungemia have been reported, mainly in immunocompromised individuals.
Contraindications
Severely immunocompromised individuals, those with severe acute pancreatitis, central venous catheters, or damaged heart valves should avoid probiotics or use them cautiously under medical supervision. Premature infants and people with short bowel syndrome should only use probiotics if recommended and supervised by a physician.
Drug Interactions
May interact with certain antibiotics, reducing the effectiveness of the probiotic. Administer Lactobacillus at least two hours before or after antibiotics. Limited information is available on other drug interactions.
Pregnancy and Breastfeeding
Generally considered safe during pregnancy and breastfeeding. Some strains may even have beneficial effects for the mother and infant, like reduced risk of eczema. However, consult with a physician before use.
Drug Profile Summary
Mechanism of Action: Alters gut microbiome, competes with pathogens, and influences immune response.
Side Effects: Bloating, gas, diarrhea (rarely systemic infections).
Contraindications: Immunocompromised individuals, severe pancreatitis, central venous catheters, and other specific conditions.
Drug Interactions: Certain antibiotics.
Pregnancy & Breastfeeding: Generally safe, consult a physician.
Dosage: Varies greatly. 1-15 billion CFUs daily for adults, less for children.
Monitoring Parameters: Not routinely monitored.
Popular Combinations
Often combined with other probiotics like Bifidobacterium or Streptococcus for synergistic effects. Prebiotics may also be added to promote growth of beneficial bacteria.
Precautions
Consult a doctor before using in patients with underlying health conditions or those taking other medications. Start with a lower dose and gradually increase as tolerated. Stop use and consult a doctor if severe side effects appear.
FAQs
Q1: What is the recommended dosage for Lactobacillus?
A: The dosage varies based on the specific strain and condition. For adults, a daily dose between 1 and 15 billion CFUs is typical for general gut health. Higher doses may be needed for certain conditions. For children and infants, lower doses should be used under pediatric supervision.
Q2: Is Lactobacillus safe during pregnancy?
A: Generally yes, but medical advice should be sought before using any probiotic during pregnancy.
Q3: What are the common side effects of Lactobacillus?
A: Bloating, gas, and mild diarrhea are the most common side effects, typically transient.
Q4: Can Lactobacillus interact with other medications?
A: Yes, it can interact with certain antibiotics, decreasing the probiotic’s effectiveness. It should be taken at least two hours apart from antibiotics. Limited data exists on other drug interactions.
Q5: How does Lactobacillus work to improve gut health?
A: Lactobacillus produces lactic acid, creating an acidic gut environment that inhibits the growth of harmful bacteria. It also competes with pathogens for nutrients and space and modulates the immune system.
Q6: Are all Lactobacillus strains the same?
A: No, various Lactobacillus species exist with diverse properties and applications. The effects and ideal dosages differ between strains.
Q7: Can Lactobacillus be used to treat vaginal infections?
A: Yes, some Lactobacillus species are effective in treating vaginal infections, often administered orally or vaginally.
Q8: Can Lactobacillus prevent antibiotic-associated diarrhea?
A: Yes, several Lactobacillus strains, particularly Lactobacillus rhamnosus GG, have shown effectiveness in preventing antibiotic-associated diarrhea.
Q9: Who should not take Lactobacillus?
A: Severely immunocompromised individuals, those with severe acute pancreatitis, and other serious medical conditions should avoid probiotics or use them with caution under medical supervision.
Q10: What are the long-term effects of Lactobacillus use?
A: No significant long-term adverse effects have been documented when Lactobacillus is taken as directed.
