[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Pharmacology](https://durgical.com/en/pharmacology/) › Oxazolidinones

[Pharmacology](https://durgical.com/en/pharmacology/) · Class

# Oxazolidinones

Synthetic antibiotics that block the start of bacterial protein synthesis; active against MRSA and VRE, also by mouth.

Updated 2026-11-01

## What they are

A fully synthetic class (linezolid, tedizolid) for resistant gram-positive infections: MRSA, vancomycin-resistant enterococci and penicillin-resistant pneumococci. Linezolid is also part of some regimens for drug-resistant tuberculosis.

## Mechanism of action

They bind the 23S rRNA of the 50S ribosomal subunit, at the peptidyl-transferase centre, and prevent formation of the functional 70S initiation complex. Because the site is unique, there is no cross-resistance with other protein-synthesis inhibitors. They are bacteriostatic against staphylococci and enterococci and bactericidal against most streptococci.

Target: 23S rRNA of the bacterial 50S ribosomal subunit

## Key points

- Linezolid is a weak MAO inhibitor: serotonin syndrome with SSRIs and other serotonergic drugs, and pressor reactions with sympathomimetics or large amounts of tyramine.
- Myelosuppression, mainly thrombocytopenia, grows with treatment length: blood counts are checked weekly.
- Long courses can cause peripheral and optic neuropathy and lactic acidosis, attributed to inhibition of mitochondrial protein synthesis.
- Oral bioavailability is close to complete, so switching from IV to oral needs no change.
- No useful activity against gram-negative bacteria.

## Drugs in this class

- [**Linezolid** An oral or IV oxazolidinone for MRSA, VRE and drug-resistant TB; watch platelets, nerves and serotonin-drug… Peptidyl-transferase centre of the 23S rRNA, 50S ribosomal subunit](https://durgical.com/en/pharmacology/linezolid/)
- [**Tedizolid** A once-daily oxazolidinone, oral or IV, for gram-positive skin infections including MRSA; similar to linezolid. Peptidyl-transferase centre of the 23S rRNA, 50S ribosomal subunit](https://durgical.com/en/pharmacology/tedizolid/)

## Test yourself

Think of the answer, then tap the question to see it.

## At which step do oxazolidinones block protein synthesis?

At initiation: by binding the 23S rRNA of the 50S subunit they prevent assembly of the functional 70S initiation complex.

## Why can linezolid cause serotonin syndrome?

It weakly inhibits monoamine oxidase, so serotonergic drugs such as SSRIs accumulate their effect.

## Which toxicities appear mainly with long linezolid courses?

Myelosuppression (especially thrombocytopenia), peripheral and optic neuropathy, and lactic acidosis.

[Add to my cards (3)](https://durgical.app/estudiar/?add=/en/pharmacology/classes/oxazolidinones/)

[← All of pharmacology](https://durgical.com/en/pharmacology/)

Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.

Sources: Goodman & Gilman's The Pharmacological Basis of Therapeutics, 14th ed., ch. 60 (McGraw Hill, 2023); [DailyMed - LINEZOLID tablet, film coated](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=7402aa01-50de-46c8-a341-d30da5b32b1c) (DailyMed (U.S. National Library of Medicine), 2026); [RCSB PDB - 4WFA: The crystal structure of the large ribosomal subunit of Staphylococcus aureus in complex with linezolid](https://www.rcsb.org/structure/4WFA) (RCSB Protein Data Bank, 2026).

## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake

Representative model, for educational purposes only.

---
Source: https://durgical.com/en/pharmacology/classes/oxazolidinones/
License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/pharmacology/classes/oxazolidinones/