Non depolarizing muscle relaxants are potentiated by all except
Phenytoin and other anticonvulsants are enzyme inducers and accelerates metabolism of non-depolarizing neuromuscular blockers. Drug administered in the Perioperative period may enhance the effects of Non depolarizing neuromuscular blockers . 1. Volatile anesthetics All potent inhalational agent potentiate NMB- Halothane, Isoflurane, Sevoflurane & Desflurane. Mechanism- i Depression of the CNS, which decreases the tone of skeletal muscle. ii Decreases sensitivity of postjunctional membranes to depolarization. 2. ANTIBIOTICS Aminoglycerides, Tetracycline & Polypeptide Mechanism - effects prejunctinal membrane & release of Acetylcholine. 3. Local Anaesthetics Depending on dose, local anesthetics interface with the prejunctional release of acetyle chlorine, stabilize postjunctional membrane and directly depress skeletal muscle fibres. 4. Antiarrythmic Lidocaine& Quinidine 5. Furosemide . 6. Magnesium . 7. Lithium 8. Cyclosporine 9. Coicosteroid 10.Hypothermia 11. Acidosis Drugs antagonizing the effect of NMB 1) Anticonvulsant 2) Burn injury 3) Hemiplegia /Paresis Potassium Acute decrease in the Extracellular K+ increases transmembrane potential causing hydropolarization of cell membranes. Thus -Resistance to depolarizing increased sensitivity to non depolarizing Acute increase decreases transmembrane potential and thus paially depolarize cell membrane Thus - increases the effect of depolarizing - Opposes non depolarizing.
Phenytoin
Amino glycoside antibiotics
Polymyxin
Quinidine
Neuromuscular Blocker