What is bacterial lysates OM-85 used for?

bacterial lysates OM-85 is evaluated for the following indications with varying evidence strength: Prevention of recurrent respiratory infections (evidence tier D), COVID-19 (evidence tier F). See the full indication matrix with dosing and citations above on this page.

What are the side effects of bacterial lysates OM-85?

Common side effects of bacterial lysates OM-85 (≥ 1 in 100): Gastrointestinal upset (nausea, abdominal pain, diarrhoea), Headache, Rash. See the Safety section for uncommon and serious reactions.

Is bacterial lysates OM-85 safe during pregnancy?

Pregnancy data are limited. Avoid use without clear indications.

Who should not take bacterial lysates OM-85?

bacterial lysates OM-85 is contraindicated in: Hypersensitivity to any component; Age under 6 months (pediatric formulation), under 12 years (adult formulation); Acute intestinal infections. Full list in the Safety section.

bacterial lysates OM-85

Other immunostimulants

ATC code: L03AX-OM85 (Bacterial lysate OM-85 systemic (local code))

Mechanism of action

Lyophilised lysates of 8 bacterial species: Haemophilus influenzae, Streptococcus pneumoniae, Klebsiella pneumoniae, Klebsiella ozaenae, Staphylococcus aureus, Streptococcus pyogenes, Streptococcus viridans, Moraxella catarrhalis. The manufacturer claims dendritic cell and T-lymphocyte activation, enhanced secretory IgA synthesis, and modulation of cellular immune response. Unlike many Russian 'immunomodulators', OM-85 has a limited international evidence base: a 2012 Cochrane review found a possible reduction in URI episodes in children, but with high risk of bias.

Indications

Prevention of recurrent respiratory infections

Individual decision

A 2012 Cochrane review of bacterial lysates in children showed a possible reduction of approximately 1.2 URI episodes over 6 months. Authors noted high risk of bias in most included trials and result heterogeneity. The 2023 ERS guideline mentions OM-85 as an option for recurrent respiratory infections in children but without a strong recommendation. There are no data on long-term outcomes – severity, antibiotic use, or hospitalisations.

Adult use is a separate topic with weaker evidence. Decisions are individual with realistic expectations: the effect is limited and long-term benefits have not been demonstrated.

bacterial lysates OM-85

Mechanism of action

Indications

Prevention of recurrent respiratory infections

COVID-19

Non-specific immune boosting and respiratory infection prevention

Practical notes

Russian practice note

Context

Safety

Contraindications

Serious adverse effects

Common adverse effects

Pregnancy

Frequently asked