Not applicable.
There are no further relevant data.
Lidocaine is a local anaesthetic of the amide type. Like other local anaesthetics, lidocaine impairs the generation and conduction of the nerve impulses by slowing depolarisation. This results from blocking of the large transient increase in permeability of the cell membrane to sodium ions that follows initial depolarisation of the membrane. Lidocaine also reduces the permeability of the resting axon to potassium and to sodium ions.
Chlorhexidine is a bisbiguanide antiseptic and disinfectant which is bactericidal or bacteriostatic against a wide range of Gram-positive and Gram-negative bacteria. It is more effective against Gram-positive than Gram-negative bacteria and some species of Pseudomonas and Proteus have low susceptibility. It is relatively ineffective against mycobacteria. It inhibits some viruses and is active against some fungi.
Covonia Throat Spray is applied topically for local action in the throat. On swallowing the spray solution or saliva, small amounts may reach the digestive system and some may be absorbed from the oral and pharyngeal mucosa.
Lidocaine is readily absorbed from oral mucous membranes, the gastrointestinal tract and through damaged skin. Absorption through intact skin is poor. Presystemic metabolism is extensive and bioavailability is only about 35% after oral administration. Following absorption, lidocaine is rapidly distributed to all body tissues. It crosses the placenta and blood-brain barrier. Approximately 65% is bound to plasma protein. It has a plasma half-life of 1.6 hours. Lidocaine is largely metabolised in the liver. Any alteration in liver function or hepatic blood flow can have a significant effect on its pharmacokinetics and dosage requirements. Metabolism in the liver is rapid and approximately 90% of a given dose is dealkylated to form monoethylglycinexylidide (MEGX) and glycinexylidide (GX); both of which may contribute to its therapeutic and toxic effects. Further metabolism occurs and metabolites are excreted in the urine with less than 10% of unchanged lidocaine.
Chlorhexidine is poorly absorbed from mucous membranes, intact skin and the gastrointestinal tract. It is only minimally metabolised by the liver and is excreted through bile. Urinary excretion is very low.
Not applicable.
