Abmenor Tablets
Composition
| Pregabalin: | 75 mg |
| Nortriptyline: | 10 mg |
| Methylcobalamin: | 1500 mcg |
Mechanism of action
It is believed that nortriptyline either inhibits the reuptake of the neurotransmitter serotonin at the neuronal membrane or acts at beta-adrenergic receptors. It displays a more selective reuptake inhibition for noradrenaline, which may explain the relief and improvement of biological symptoms with nortriptyline therapy.
As with other TCAs, nortriptyline displays affinity for other receptors including mACh receptors, histamine receptors and 5-HT receptors. Antimuscarinic effects upon binding to mAChR are responsible for various side effects of TCAs.
By binding pre-synaptically to the alpha2-delta subunit of voltage-gated calcium channels in the central nervous system, Pregabalin modulates the release of several excitatory neurotransmitters including glutamate, substance-P, norepinephrine, and calcitonin gene related peptide. In addition, Pregabalin prevents the alpha2-delta subunit from being trafficked from the dorsal root ganglia to the spinal dorsal horn, which may also contribute to the mechanism of action. Although Pregabalin is a structural derivative of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA), it does not bind directly to GABA or benzodiazepine receptors.4.2Pharmacodynamic properties
Nortriptyline is a tricyclic antidepressant of the dibenzocycloheptene type and is the active metabolite of amitriptyline. It is an inhibitor of pre-synaptic noradrenaline reuptake than of serotonin, and is less anticholinergic than amitriptyline whilst having stronger antihistaminergic effects. Nortriptyline has been observed to increase the pressor effect of norepinephrine but blocks the pressor response of phenethylamine. Although the structure of pregabalin is similar to gamma-aminobutyric acid (GABA), it does not bind to GABA receptors. Instead, it binds the alpha2-delta subunit of presynaptic voltage-gated calcium channels in the central nervous system. Pregabalin does not modulate dopamine receptors, serotonin receptors, opiate receptors, sodium channels or cyclooxygenase activity.4.3Pharmacokinetic properties
Nortriptyline
Absorption
As with other TCAs, notriptyline is well absorbed from the GI tract. Peak plasma concentrations occur within 4-8.8 hours following oral administration, with the mean time of 5.5 hours. The mean oral bioavailability is 51% Protein binding Plasma protein binding is approximately 93%MetabolismNortriptyline undergoes hepatic metabolism via the same pathway as other TCAs, where it is metabolized via demethylation and hydroxylation followed by conjugation with glucuronic acid. The metabolism is subject to genetic polymorphism (CYP2D6). The main active metabolite is 10-hydroxynortriptyline exists in a cis and a trans form, where the trans form is dominant and more pharmacologically potent. N-demethylnortriptyline is also formed to some extent. The metabolites have the same pharmacological profile as nortriptyline, but are weaker. 10-hydroxynortriptyline dominates in the plasma, but most of the metabolites are conjugated
Excretion
Nortriptyline and its metabolites are mainly excreted in the urine, where only small amounts (2%) of the total drug is recovered as unchanged parent compound. Approximately one-third of a single orally administered dose is excreted in urine within 24 hours. Small amounts are excreted in faeces via biliary elimination.
Pregabalin
Absorption
After oral dosing administered in the fasted state, pregabalin absorption is rapid, and extensive.
Pregabalin oral bioavailability is reported to be ≥90% regardless of the dose.
Cmax is attained within 1.5 hours after single or multiple doses, and steady state is attained within 24-48 hours with repeated administration.
Both Cmax and AUC appear to be dose proportional.
Protein binding
Pregabalin is not plasma protein bound.
Metabolism
Less than 2% of pregabalin is metabolized and it is excreted virtually unchanged in the urine
Excretion
Pregabalin is almost exclusively eliminated in the urine
Methylcobalamin
Absorption
Evidence indicates Methylcobalamin is utilized more efficiently than cyanocobalamin to increase levels of one of the coenzyme forms of vitamin B12. Experiments have demonstrated similar absorption of Methylcobalamin following oral administration. The quantity of cobalamin detected following a small oral dose of mecobalamin is similar to the amount detected following the administration of cyanocobalamin, but significantly more cobalamin accumulates in liver tissue, which is associated with mecobalamin intake.
Excretion
Human urinary excretion of Methylcobalamin is about one third that of a similar dose of cyanocobalamin, indicating substantially greater tissue retention.
Indications, Dosage and Contraindications
Indications
- Diabetic Peripheral Neuropathy
- Low Back Pain
- Postherpetic Neuralgia
- Fibromyalgia
- Spinal Cord Injury
Dosage
1 Tablet, once a day.
Contraindications
Contraindicated in patient with hypersensitivity to any component of tablets and history of urinary retention – BPH
Special warnings and precautions
Do not drink alcohol while taking Abmenor Tablets. It can increase the effects of alcohol, which could be dangerous.
Grapefruit and grapefruit juice may also interact with this medicine and cause unwanted side effects.
Use of Abmenor tablets can make patient more prone to sunburns. Hence avoid exposure to sunlight or tanning beds. Wear protective clothing and use sunscreen when outdoors during daytime.
Use in special population
Liver impairment: Not recommended.
Renal failure
Use with caution.
Pregnancy and lactation
Category C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.
Effects on ability to drive and use machine Abmenor Tablets may impair thinking or reactions. Patients should be cautioned against engaging in activities requiring complete mental alertness, and motor coordination such as operating machinery.
Undesirable effects
Sedation, Drowsiness and Dizziness
Weight Gain
Dry mouth, blurred vision, increased intraocular pressure, constipation Hypotension, Syncope, Palpitations, Myocardial Infarction & Arrhythmias
Packaging Information
Abmenor Tablets: Pack of 10 Tablets
Store in a cool and dry place. Store out of sight and reach of the children.
Got a question?
We’d love to talk about how we can help you.
