Product Information
Registration Status: ActiveCO-PHENYLCAINE FORTE SPRAY is approved to be sold in Singapore with effective from 1995-06-19. It is marketed by ZIWELL MEDICAL (S) PTE LTD, with the registration number of SIN08214P.
This product contains Lignocaine 50mg/ml, and Phenylephrine 5mg/ml in the form of SPRAY. It is approved for NASAL use.
This product is manufactured by F H FAULDING & CO LTD in AUSTRALIA.
It is an Over-the-counter Medicine that can be freely obtained from any retailer
Description
A local anesthetic and cardiac depressant used as an antiarrhythmia agent. Its actions are more intense and its effects more prolonged than those of procaine but its duration of action is shorter than that of bupivacaine or prilocaine. [PubChem]
Indication
For production of local or regional anesthesia by infiltration techniques such as percutaneous injection and intravenous regional anesthesia by peripheral nerve block techniques such as brachial plexus and intercostal and by central neural techniques such as lumbar and caudal epidural blocks.
Mechanism of Action
Lidocaine stabilizes the neuronal membrane by inhibiting the ionic fluxes required for the initiation and conduction of impulses thereby effecting local anesthetic action. Lidocaine alters signal conduction in neurons by blocking the fast voltage gated sodium (Na+) channels in the neuronal cell membrane that are responsible for signal propagation. With sufficient blockage the membrane of the postsynaptic neuron will not depolarize and will thus fail to transmit an action potential. This creates the anaesthetic effect by not merely preventing pain signals from propagating to the brain but by aborting their birth in the first place.
Pharmacokinetics
- Absorption
- Information derived from diverse formulations, concentrations and usages reveals that lidocaine is completely absorbed following parenteral administration, its rate of absorption depending, for example, upon various factors such as the site of administration and the presence or absence of a vasoconstrictor agent.
- Distribution
- * 0.7 to 2.7 L/kg [healthy volunteers]
- Metabolism
- Primarily hepatic.
- Elimination
Clearance
* 0.64 +/- 0.18 L/min
Toxicity
The oral LD 50 of lidocaine HCl in non-fasted female rats is 459 (346-773) mg/kg (as the salt) and 214 (159-324) mg/kg (as the salt) in fasted female rats. Symptoms of overdose include convulsions, hypoxia, acidosis, bradycardia, arrhythmias and cardiac arrest.
Active Ingredient/Synonyms
2-(Diethylamino)-2',6'-acetoxylidide | 2-(Diethylamino)-N-(2,6-dimethylphenyl)acetamide | alpha-diethylamino-2,6-dimethylacetanilide | Lignocaine | α-diethylamino-2,6-dimethylacetanilide | Lidocaine |
Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.
Description
Phenylephrine is a sympathomimetic amine that acts predominantly on α-adrenergic receptors. It is mainly used to treat nasal congestion, but may also be useful in treating hypotension and shock, hypotension during spinal anaesthesia, prolongation of spinal anaesthesia, paroxysmal supraventricular tachycardia, symptomatic relief of external or internal hemorrhoids, and to increase blood pressure as an aid in the diagnosis of heart murmurs.
Indication
Phenylephrine is mainly used to treat nasal congestion, but may also be useful in treating hypotension and shock, hypotension during spinal anaesthesia, prolongation of spinal anaesthesia, paroxysmal supraventricular tachycardia, symptomatic relief of external or internal hemorrhoids, and to increase blood pressure as an aid in the diagnosis of heart murmurs.
Mechanism of Action
In general, α1-adrenergic receptors mediate contraction and hypertrophic growth of smooth muscle cells. α1-receptors are 7-transmembrane domain receptors coupled to G proteins, Gq/11. Three α1-receptor subtypes, which share approximately 75% homology in their transmembrane domains, have been identified: α1A (chromosome 8), α1B (chromosome 5), and α1D (chromosome 20). Phenylephrine appears to act similarly on all three receptor subtypes. All three receptor subtypes appear to be involved in maintaining vascular tone. The α1A-receptor maintains basal vascular tone while the α1B-receptor mediates the vasocontrictory effects of exogenous α1-agonists. Activation of the α1-receptor activates Gq-proteins, which results in intracellular stimulation of phospholipases C, A2, and D. This results in mobilization of Ca2+ from intracellular stores, activation of mitogen-activated kinase and PI3 kinase pathways and subsequent vasoconstriction. Phenylephrine produces its local and systemic actions by acting on α1-adrenergic receptors peripheral vascular smooth muscle. Stimulation of the α1-adrenergic receptors results in contraction arteriolar smooth muscle in the periphery. Phenylephrine decreases nasal congestion by acting on α1-adrenergic receptors in the arterioles of the nasal mucosa to produce constriction; this leads to decreased edema and increased drainage of the sinus cavities.
Pharmacokinetics
- Absorption
- Completely absorbed after oral administration. It has a reduced bioavailability (compared to pseudoephedrine) following oral administration due to significant first-pass metabolism in the intestinal wall. Compared to IV administration, bioavailability is approximately 38%. Peak serum concentrations are achieved approximately 0.75-2 hours following oral administration. Phenylephrine should be administered parenterally to achieve cardiovascular effects. Occasionally, systemic effects are observed following oral inhalation.
- Distribution
- Metabolism
- Undergoes extensive first-pass metabolism in the intestinal wall and extensive metabolism in the liver. Sulfate conjugation, primarily in the intestinal wall, and oxidative metabolism by monoamine oxidase (MAO) represent the principle routes of metabolism. Glucuronidation occurs to a lesser extent. Phenylephrine and its metabolites are mainly excreted in urine/ .
- Elimination
Active Ingredient/Synonyms
(-)-m-Hydroxy-alpha-(methylaminomethyl)benzyl alcohol | (-)-m-Hydroxy-α-(methylaminomethyl)benzyl alcohol | Benzenemethanol, 3-hydroxy-.alpha.-[(methylamino)methyl]-, (R)- | Benzenemethanol, 3-hydroxy-alpha-((methylamino)methyl)-, (R)- | Benzyl alcohol, m-hydroxy-alpha-((methylamino)methyl)-, (-)- | Fenilefrina | l-(3-Hydroxyphenyl)-N-methylethanolamine | Phenylephrine | Phenylephrinum | R(-)-Phenylephrine | Phenylephrine |
Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.