NIF-TEN CAPSULE

Product Information

Registration Status: Inactive

THIS PRODUCT HAS BEEN DEREGISTERED!

NIF-TEN CAPSULE is approved to be sold in Singapore with effective from 1988-06-05. It is marketed by ASTRAZENECA SINGAPORE PTE LTD, with the registration number of SIN00798P.

This product contains Atenolol 50mg, and Nifedipine 20mg in the form of CAPSULE. It is approved for ORAL use.

This product is manufactured by Corden Pharma GmbH in GERMANY.

It is a Prescription Only Medicine that can only be obtained from a doctor or a dentist, or a pharmacist with a prescription from a Singapore-registered doctor or dentist.

Atenolol
Nifedipine

Description

A cardioselective beta-adrenergic blocker possessing properties and potency similar to propranolol, but without a negative inotropic effect.

Indication

For the management of hypertention and long-term management of patients with angina pectoris

Mechanism of Action

Like metoprolol, atenolol competes with sympathomimetic neurotransmitters such as catecholamines for binding at beta(1)-adrenergic receptors in the heart and vascular smooth muscle, inhibiting sympathetic stimulation. This results in a reduction in resting heart rate, cardiac output, systolic and diastolic blood pressure, and reflex orthostatic hypotension. Higher doses of atenolol also competitively block beta(2)-adrenergic responses in the bronchial and vascular smooth muscles.

Pharmacokinetics

Absorption
Approximately 50% of an oral dose is absorbed from the gastrointestinal tract, the remainder being excreted unchanged in the feces.
Distribution
Metabolism
Hepatic (minimal)
Elimination

Toxicity

LD50=2000-3000 mg/kg(orally in mice). Symptoms of an atenolol overdose include a slow heart beat, shortness of breath, fainting, dizziness, weakness, confusion, nausea, and vomiting.

Active Ingredient/Synonyms

1-p-Carbamoylmethylphenoxy-3-isopropylamino-2-propanol | 2-(p-(2-Hydroxy-3-(isopropylamino)propoxy)phenyl)acetamide | 4-(2-Hydroxy-3-((1-methylethyl)amino)propoxy)benzeneacetamide | Atenololum | Atenolol |


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

Nifedipine has been formulated as both a long- and short-acting 1,4-dihydropyridine calcium channel blocker. It acts primarily on vascular smooth muscle cells by stabilizing voltage-gated L-type calcium channels in their inactive conformation. By inhibiting the influx of calcium in smooth muscle cells, nifedipine prevents calcium-dependent myocyte contraction and vasoconstriction. A second proposed mechanism for the drug’s vasodilatory effects involves pH-dependent inhibition of calcium influx via inhibition of smooth muscle carbonic anhydrase. Nifedipine is used to treat hypertension and chronic stable angina.

Indication

For the management of vasospastic angina, chronic stable angina, hypertension, and Raynaud's phenomenon. May be used as a first line agent for left ventricular hypertrophy and isolated systolic hypertension (long-acting agents).

Mechanism of Action

Nifedipine decreases arterial smooth muscle contractility and subsequent vasoconstriction by inhibiting the influx of calcium ions through L-type calcium channels. Calcium ions entering the cell through these channels bind to calmodulin. Calcium-bound calmodulin then binds to and activates myosin light chain kinase (MLCK). Activated MLCK catalyzes the phosphorylation of the regulatory light chain subunit of myosin, a key step in muscle contraction. Signal amplification is achieved by calcium-induced calcium release from the sarcoplasmic reticulum through ryanodine receptors. Inhibition of the initial influx of calcium inhibits the contractile processes of smooth muscle cells, causing dilation of the coronary and systemic arteries, increased oxygen delivery to the myocardial tissue, decreased total peripheral resistance, decreased systemic blood pressure, and decreased afterload. The vasodilatory effects of nifedipine result in an overall decrease in blood pressure.

Pharmacokinetics

Absorption
Rapidly and fully absorbed following oral administration.
Distribution
Metabolism
Hepatic metabolism via cytochrome P450 system. Predominantly metabolized by CYP3A4, but also by CYP1A2 and CYP2A6 isozymes.
Elimination

Toxicity

Symptoms of overdose include dizziness, drowsiness, nausea, severe drop in blood pressure, slurred speech, and weakness. LD50=494 mg/kg (orally in mice); LD50=1022 mg/kg (orally in rats)

Active Ingredient/Synonyms

4-(2'-Nitrophenyl)-2,6-dimethyl-1,4-dihydropyridin-3,5-dicarbonsaeuredimethylester | Adapine | Nifecard | Nifecor | Nifedipine | Nifedipino | Nifedipinum | Nifedipres | Nifedipine |


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