MENDICOF SYRUP (REVISED FORMULA)

Product Information

Registration Status: Active

MENDICOF SYRUP (REVISED FORMULA) is approved to be sold in Singapore with effective from 2001-05-15. It is marketed by SUNWARD PHARMACEUTICAL PTE LTD, with the registration number of SIN11516P.

This product contains Dexchlorpheniramine 2mg/5ml,Dextromethorphan 15mg/5ml, and Pseudoephedrine 30mg/5ml in the form of SYRUP. It is approved for ORAL use.

This product is manufactured by SUNWARD PHARMACEUTICAL PTE LTD in SINGAPORE.

It is a Pharmacy Only Medicine that can be obtained from a pharmacist at a retail pharmacy.

Dexchlorpheniramine
Dextromethorphan
Pseudoephedrine

Description

Dexchlorpheniramine is the S-enantiomer of chlorpheniramine which is a 1st generation anti-histamine. Dexchlorpheniramine has more pharmacological activity than the R and so is more potent than the racemic mixture.

Indication

Dexchlorpheniramine can be used in the treatment of perennial and seasonal allergic rhinitis, vasomotor rhiniti, allergic conjunctivitis due to inhalant allergens and foods, mild uncomplicated allergic skin manifestations of urticaria and angioedema, amelioration of allergic reactions to blood or plasma, and dermographism.

Mechanism of Action

Competes with histamine for H1-receptor sites on effector cells in the gastrointestinal tract, blood vessels, and respiratory tract. Dexchlorpheniramine is the predominant active isomer of chlorpheniramine and is approximately twice as active as the racemic compound.

Pharmacokinetics

Absorption
Oral bioavailability in rats 40.5%
Distribution
321L
Metabolism
Hepatic metabolism. Major metabolism by CYP 2D6 and minor metabolism by 3A4, 2C11 and 2B1.
Elimination

Clearance

9.8L/h

Toxicity

Central nervous system depression

Active Ingredient/Synonyms

Dexchlorpheniramine maleate | Dexchlorpheniramine maleate |


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

The d-isomer of the codeine analog of levorphanol. Dextromethorphan shows high affinity binding to several regions of the brain, including the medullary cough center. This compound is an NMDA receptor antagonist (receptors, N-methyl-D-aspartate) and acts as a non-competitive channel blocker. It is one of the widely used antitussives, and is also used to study the involvement of glutamate receptors in neurotoxicity. [PubChem]

Indication

For treatment and relief of dry cough.

Mechanism of Action

Dextromethorphan is an opioid-like drug that binds to and acts as antagonist to the NMDA glutamatergic receptor, it is an agonist to the opioid sigma 1 and sigma 2 receptors, it is also an alpha3/beta4 nicotinic receptor antagonist and targets the serotonin reuptake pump. Dextromethorphan is rapidly absorbed from the gastrointestinal tract, where it enters the bloodstream and crosses the blood-brain barrier. The first-pass through the hepatic portal vein results in some of the drug being metabolized into an active metabolite of dextromethorphan, dextrorphan, the 3-hydroxy derivative of dextromethorphan.

Pharmacokinetics

Absorption
Rapidly absorbed from the gastrointestinal tract.
Distribution
Metabolism
Hepatic. Rapidly and extensively metabolized to dextrorphan (active metabolite). One well known metabolic catalyst involved is a specific cytochrome P450 enzyme known as 2D6, or CYP2D6.
Elimination

Active Ingredient/Synonyms

(+)-dextromethorphan | D-methorphan | delta-Methorphan | Dex | Dextromethorfan | Dextromethorphan | Dextrométhorphane | Dextromethorphanum | Dextrometorfano | DM | Dextromethorphan |


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

An alpha- and beta-adrenergic agonist that may also enhance release of norepinephrine. It has been used in the treatment of several disorders including asthma, heart failure, rhinitis, and urinary incontinence, and for its central nervous system stimulatory effects in the treatment of narcolepsy and depression. It has become less extensively used with the advent of more selective agonists.

Indication

For the treatment of nasal congestion, sinus congestion, Eustachian tube congestion, and vasomotor rhinitis, and as an adjunct to other agents in the optimum treatment of allergic rhinitis, croup, sinusitis, otitis media, and tracheobronchitis. Also used as first-line therapy of priapism.

Mechanism of Action

Pseudoephedrine acts directly on both alpha- and, to a lesser degree, beta-adrenergic receptors. Through direct action on alpha-adrenergic receptors in the mucosa of the respiratory tract, pseudoephedrine produces vasoconstriction. Pseudoephedrine relaxes bronchial smooth muscle by stimulating beta2-adrenergic receptors. Like ephedrine, pseudoephedrine releasing norepinephrine from its storage sites, an indirect effect. This is its main and direct mechanism of action. The displaced noradrenaline is released into the neuronal synapse where it is free to activate the postsynaptic adrenergic receptors.

Pharmacokinetics

Absorption
Pseudoephedrine is readily and almost completely absorbed from the GI tract and there is no evidence of first-pass metabolism.
Distribution
Metabolism
Hepatic.
Elimination

Toxicity

Common adverse reactions include nervousness, restlessness, and insomnia. Rare adverse reactions include difficult/painful urination, dizziness/lightheadedness, heart palpitations, headache, increased sweating, nausea/vomiting, trembling, troubled breathing, unusual paleness, and weakness.

Active Ingredient/Synonyms

(+) threo-2-(methylamino)-1-phenyl-1-propanol | (+)-(1S,2S)-Pseudoephedrine | (+)-Pseudoephedrine | (+)-psi-Ephedrine | (+)-threo-Ephedrine | d-Isoephedrine | d-Pseudoephedrine | d-psi-2-Methylamino-1-phenyl-1-propanol | d-psi-Ephedrine | Isoephedrine | L-(+)-Pseudoephedrine | L(+)-psi-Ephedrine | Pseudoefedrina | pseudoéphédrine | Pseudoephedrine D-form | Pseudoephedrinum | Psi-ephedrin | Psi-ephedrine | trans-Ephedrine | ψ-ephedrine | Pseudoephedrine |


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.

References

  1. Health Science Authority of Singapore - Reclassified POM
  2. Drugbank