[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Pharmacology](https://durgical.com/en/pharmacology/) › [Pleuromutilins](https://durgical.com/en/pharmacology/classes/pleuromutilins/) › Lefamulin # Lefamulin ## Pleuromutilins? Pleuromutilins ## Pregnancy: avoid? Avoided in pregnancy: it caused malformations in animals and has not been studied in pregnant women. A negative pregnancy test is required before starting. First systemic pleuromutilin, oral or IV, for community-acquired pneumonia: covers pneumococcus and atypicals. Prolongs the QT interval. Updated Nov 1, 2026 ## Quick facts **Group** [Pleuromutilins](https://durgical.com/en/pharmacology/classes/pleuromutilins/) **Target** Bacterial ribosome, 50S subunit (peptidyl transferase centre) **Key effects** Diarrhoea · Infusion-site reactions **Monitor** ECG in people with long QT **ATC** J01XX12 No doses: the clinician sets them by the current guideline. On this page - The basics Mechanism of action - Indications - Adverse effects - Pharmacokinetics - Memory aid - Clinical What the labels mean - Safety Contraindications - Key interactions - What is monitored - Administration and safety - Pregnancy and breastfeeding - Nursing care - Study Test yourself - Connections Connections ## Mechanism of action ◆**Bacterial ribosome, 50S subunit (peptidyl transferase centre)**Lefamulin ⓘ The figure shows lefamulin bound to the 50S ribosomal subunit of Staphylococcus aureus. **Target in 3D:** Bacterial ribosome, 50S subunit (peptidyl transferase centre). PDB structure 5HL7 (RCSB PDB, public domain). [View the structure at RCSB PDB](https://www.rcsb.org/structure/5HL7) · Drag to rotate · pinch to zoom Lefamulin binds the peptidyl transferase centre of the 50S subunit, near the A and P sites. The binding pocket closes over it and keeps transfer RNA from sitting properly, so no peptide bond forms. It is bactericidal against respiratory gram-positives and active against Mycoplasma, Legionella and Chlamydophila. - Enters the 50S peptidyl transferase centre - The pocket closes around the drug - tRNA cannot settle in the A and P sites - No peptide bond forms ## Indications - Community-acquired bacterial pneumonia in adults [Community-acquired pneumonia →](https://durgical.com/en/conditions/community-acquired-pneumonia/) ## Adverse effects ### Common - Diarrhoea, nausea and vomiting (oral form) - Infusion-site reactions (IV form) ### Serious (rare, important) - QT interval prolongation - Clostridioides difficile diarrhoea, even two months or more later ## Contraindications - Allergy to lefamulin or other pleuromutilins (retapamulin) - Use together with pimozide ## Key interactions **Strong CYP3A4 inducers and inhibitors** Lower or raise lefamulin levels; avoided or used with caution. **Pimozide and other QT-prolonging drugs** Additive QT prolongation; never combined with pimozide. **St John's wort** A CYP3A4 inducer that can lower its levels. ## What is monitored - ECG in people with long QT, arrhythmias or QT-prolonging drugs - Pregnancy test before starting in women who can become pregnant - Diarrhoea during and after treatment ## Administration and safety - Oral on an empty stomach: at least 1 hour before or 2 hours after a meal, with a glass of water - Tablets are swallowed whole, not split or chewed - The IV route can cause pain or phlebitis at the infusion site ## Pregnancy and breastfeeding Avoided in pregnancy: it caused malformations in animals and has not been studied in pregnant women. A negative pregnancy test is required before starting. ## Nursing care - Review the medicines for CYP3A4 inhibitors or inducers and QT-prolonging drugs - Confirm a negative pregnancy test and explain contraception during treatment and for two days after - Watch for palpitations, dizziness or fainting - Teach to finish the course ## Pharmacokinetics **Absorption** Oral with low bioavailability (about 25%), lower with food; also IV. **Distribution** Highly bound to plasma proteins. **Metabolism** Hepatic, by CYP3A4. **Elimination** Mainly in the faeces; no adjustment in kidney failure. ## Memory aid «LEFA-MULE from a mushroom»: a fungus (Pleurotus) carries community pneumonia on its back, typicals and atypicals, but it stumbles on the QT and stays out of pregnancy. ## Test yourself Think of the answer, then tap the question to see it. ## Where does lefamulin's class come from, and where does it act? It is a pleuromutilin, derived from a product of Pleurotus fungi; it acts at the peptidyl transferase centre of the 50S ribosome. ## Which test is required before starting lefamulin in a woman who can become pregnant? A negative pregnancy test, because it caused malformations in animals. ## Which enzyme metabolises lefamulin, and what does that imply? CYP3A4: strong inhibitors and inducers change its levels and are avoided or used with caution. ## Which cardiac effect means the other drugs of someone on lefamulin are reviewed? QT prolongation; it is not combined with pimozide and is watched with other QT-prolonging drugs. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/pharmacology/lefamulin/) [More Pharmacology questions →](https://durgical.com/en/practice/?f=pharmacology) ## What the labels mean **Pregnancy: avoid** Avoided in pregnancy: it caused malformations in animals and has not been studied in pregnant women. A negative pregnancy test is required before starting. ## Connections ## Related drugs 3 - [Moxifloxacin](https://durgical.com/en/pharmacology/moxifloxacin/) - [Azithromycin](https://durgical.com/en/pharmacology/azithromycin/) - [Doxycycline](https://durgical.com/en/pharmacology/doxycycline/) ## Related conditions 1 - [Community-acquired pneumonia](https://durgical.com/en/conditions/community-acquired-pneumonia/) [← Back to the class: Pleuromutilins](https://durgical.com/en/pharmacology/classes/pleuromutilins/) Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given. Sources: [Lefamulin: MedlinePlus Drug Information](https://medlineplus.gov/druginfo/meds/a619059.html) (MedlinePlus (U.S. National Library of Medicine), 2026); [The crystal structure of the large ribosomal subunit of Staphylococcus aureus in complex with lefamulin](https://www.rcsb.org/structure/5HL7) (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/lefamulin/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/pharmacology/lefamulin/