|
Somidem
DESCRIPTION
An 11
mm white caplet with 'DUO' marking.
COMPOSITION
Each tablet contains Zolpidem Tartrate 10 mg
PHARMACODYNAMICS
Zolpidem is a potent agonist with high intrinsic activity at the omega (w)1
subtype (also called the benzodiazepine 1[BZ1] subtype) of the gamma-aminobutyric
acid type (GABAA) receptorchloride ionophore complex. The receptor complex
resides on the neuronal membranes and functions in the gating of the
chloride channel, allowing the flow of chloride ions through the neuronal
membrane and into the neuron. This results in hyperpolarization, which
inhibits the firing of that neuron.
In contrast to benzodiazepines, which bind non-selectively to the omega 1,
omega 2 and omega 3 GABAA receptors, zolpidem possesses relative selectivity
for the omega 1 GABAA receptor. This preference for the omega 1 GABAA
receptor may account for zolpidem's relative lack of anticonvulsant,
myelorelaxant, and anxiolytic effects at therapeutic doses, and for the
general preservation of sleep architecture seen with zolpidem use.
PHARMACOKINETICS:
Absorption: Rapid and complete, although first-pass metabolism results in
70% bioavailability. Food may decrease the rate and extent of absorption.
Distribution: The volume of distribution (VolD) of zolpidem in healthy
volunteers was 0.54 L per kg (L/kg) following an 8 mg intravenous dose.
Zolpidem is distributed into breast milk; amounts ranging from 0.004 to
0.019% of a 20-mg oral dose were present in milk samples taken 3 hours
following administration.
Protein binding: Very high (92%).
Biotransformation: Hepatic, resulting in 3 major and several minor
metabolites.
Half-life: Elimination - 2.6 hours (range, 1.4 to 4.5 hours). The
elimination half-life of zolpidem is prolonged in the elderly and in
patients with impaired hepatic or renal function.
Onset of action: Rapid.
Time to peak concentration: 30 minutes to 2 hours; may be longer if zolpidem
is taken with food.
Peak serum concentration: Mean peak plasma concentration (Cmax) following
oral administration of 5 mg of zolpidem in healthy volunteers was 59
nanograms per mL (nanograms/mL) (0.077 micromoles per L [micromoles/L]),
with a range of 29 to 113 nanograms /mL (0.038 to 0.148 micromoles/L); Cmax
following administration of 10 mg of zolpidem was 121 nanograms/mL (0.158
micromoles/L) with a range of 58 to 272 nanograms/mL (0.076 to 0.356
micromoles/L).
Elimination
Renal - 48 to 67% of a single dose is eliminated in the urine
Fecal - 29 to 42% of a single dose is eliminated in the feces.
Unchanged zolpidem is present in trace amounts in urine and feces.
In dialysis - Not hemodialyzable.
INDICATIONS
Zolpidem is indicated for short-term treatment of insomnia. Hypnotics should
generally be limited to 7 to 10 days of use, and re-evaluation of the
patient is recommended if insomnia fails to remit after this period.
RECOMMENDED DOSAGE
Usual adult dose: Hypnotic - Oral, 10 mg at bedtime.
Note: Debilitated patients or patients with hepatic or renal function
impairment Oral, initially 5 mg at bedtime, the dosage being adjusted as
needed and tolerated. Usual adult prescribing limits: Up to 10 mg a day.
Usual pediatric dose: Children up to 18 years of age - Safety and efficacy
have not been established.
Usual geriatic dose: Hypnotic - Oral, initially 5 mg at bedtime, the dosage
being adjusted as needed and tolerated.
Usual geriatric prescribing limits: Up to 10 mg a day.
CONTRAINDICATIONS
• Sensitivity to Zolpidem.
• Alcohol intoxication, acute, with depressed vital signs.
• Sleep apnoea, established or suspected.
• Severe respiratory insufficiency.
• Sever hepatic insufficiency.
• The use of this drug is generally inadvisable in the following situation:
Children under age 18 years old, breast feeding, myasthenia.
WARNING & PRECAUTIONS
THIS DRUG MAY BE HABIT FORMING ON PROLONGED USED
Elderly patients may be more likely to experience confusion or falls while
taking zolpidem. A reduced starting dosage and careful monitoring are
recommended. In addition, geriatric patients are more likely to have
age-related renal function impairment, which may require dosage reductions.
Patient should be cautioned against engaging in hazardous occupations
requiring complete mental alertness or motor coordination such as operating
machinery or driving a motor vehicle after ingesting zolpidem, including
potential impairment of the performance of such activities that may occur
the day following ingestion of zolpidem. Zolpidem showed additive effects
when combined with alcohol and should not be taken with alcohol.
Pediatrics: Studies on the relationship of age to the effects of zolpidem
have not been performed in children up to 18 years of age. Safety and
efficacy have not been established.
Geriatrics: It has been shown zolpidem
to have an increased half-life, peak plasma concentration, and area under
the plasma concentration time curve in geriatric patients.
INTERACTION WITH OTHER MEDICATIONS
Alcohol or CNS depression-producing medications - Concurrent use may
increase the CNS effects of either these medications or zolpidem caution is
recommended, and dosage of one or both agents should be reduced.
Chlorpromazine - concurrent use may prolong elimination half-life of
chlorpromazine.
Imipramine - concurrent use may increase drowsiness and incidence of
anterograde amnesia, and decreased peak concentrations of imipramine.
USE IN PREGNANCY & LACTATION
Pregnancy: Zolpidem has not been studied in pregnant women. Teratology
studies were conducted in rats and rabbits. In rats, maternal lethargy,
ataxia and underossification of fetal bones occurred at 20 and 100 mg
base/kg dose. In rabbits, dose-related maternal sedation, decreased weight
gain occurred at all doses tested. Increase in postimplantation fetal loss
and underossification of sternbrae in viable fetuses occurred at dose of 16
mg base/kg. No frank teratogenic effects observed. Because animal
reproduction studies are not always predictive of human response, zolpidem
should be used during pregnancy only if clearly needed.
Breast feeding: Nursing mothers showed < 0.02% of a single oral dose of zolpidem was distributed into breast milk. The effect of zolpidem on the
infant is not known. In addition, in a rat study, zolpidem inhibited the
secretion of milk. The use of zolpidem in nursing mothers is not
recommended.
SIDE EFFECTS
Ataxia, confusion - in the elderly: mental depression.
Allergic reaction or rash:
Anaphylaxis - fast heartbeat, swelling of face, wheezing or difficulty in
breathing.
Falling - in the elderly
Hypotension - dizziness, light-headedness or fainting.
Paradoxical reactions, including agitation - unusual excitement or
nervousness or irritability
Hallucinations - seeing, hearing
or feeling things that are not there, or insomnia - trouble in sleeping.
Gastrointestinal: Abdominal
cramps and discomfort, gastric pain, diarrhoea, nausea, vomiting.
SYMPTOMS AND TREATMENT OF OVERDOSE
Symptoms: Ataxia, severe (clumsiness or unsteadiness); cardiovascular
compromise (slow heartbeat); diplopia (double vision) or disturbed vision;
severe dizziness; severe drowsiness; severe nausea; respiratory problems
(troubled breathing); unconsciousness; severe vomiting.
Treatment: Treatment is essentially symptomatic and supportive,
possibly including:
• Monitoring respiratory, cardiac, and CNS status and providing general
supportive therapy as indicated.
• Inducing emesis or performing gastric lavage as appropriate.
• Administering activated charcoal to increase clearance and decrease
absorption of zolpidem
• Withholding sedating drugs even if excitation occurs.
Antidote: Flumazenil may be useful in reversing zolpidem's sedative and
respiratory depression effects.
STORAGE CONDITIONS
Store below 25°C.
Protect from moisture and heat.
Keep out of reach of children.
PACK SIZE
Blister pack of 10's x 10/box
SHELF LIFE
3 years.
|
