Changes

==Pharmacokinetic Considerations==

==Pharmacokinetic Considerations==

Local anaesthetics are weak bases, and may be ionised or unisonised. The unionised form is more hydrophobic, and so will more easily cross the plasma membrane enter the cell. At body pH of 7.4, more local anaesthetic drug molecules are ionised than unionised, which is not ideal. The drugs also find it harder to enter infected tissue because it has a lower pH, giving more ionised molecules.

Local anaesthetics are weak bases and so at body pH of 7.4, more molecules are ionised than unionised. This makes it more difficult for drugs to cross the plasma membrane. Infected tissue has a lower pH than healthy tissue, causing the ratio of ionised:unionised molecules to increase. Because of this, there is poorly cellular uptake of local anaethetics in infected tisse, as they cannot cross the cell membrane. For more about the effect of pH on drugs, see the [[Pharmacokinetics|pharmacokinetics]] page.

==Side Effects and Contraindications==

==Side Effects and Contraindications==

==Drugs in this Group==

==Drugs in this Group==