Plxna

Uses

• * Anxiety disorder
• * Short term relief of anxiety
• * Anxiety associated with depression
• * Panic disorder, with or without agoraphobia.

Propranolol is used for:

• essential and renal hypertension
• angina pectoris
• long term prophylaxis after recovery from acyte myocardial infarction
• cardiac dysrhythmia
• prophylaxis of migraine
• essential tremor
• anxiety and anxiety tachycardia
• adjunctive management of thyrotoxicosis and thyrotoxic crisis
• hypertrophic obstructive cardiomyopathy
• phaeochromocytoma (with α-blocker)

Plxna is also used to associated treatment for these conditions: Anxiety, Generalized Anxiety Disorder (GAD), Panic DisorderAkathisia caused by antipsychotic use, Angina Pectoris, Atrial Fibrillation, Cardiovascular Mortality, Gastroesophageal variceal hemorrhage prophylaxis, Hemangiomas, High Blood Pressure (Hypertension), Migraine, Myocardial Infarction, Obstructive Hypertrophic Cardiomyopathy, Performance Anxiety, Pheochromocytomas, Proliferating Infantile Hemangioma, Supraventricular Arrhythmias, Tachyarrhythmia caused by Digitalis intoxication, Tachyarrhythmia caused by catecholamine excess, Thyroid Crisis, Thyrotoxicosis, Tremor caused by lithium, Tremor, Essential, Ventricular Tachycardia (VT)

How Plxna works

Alprazolam is a triazolobenzodiazepine used to treat certain anxiety and panic disorders. Alprazolam acts on benzodiazepine receptors BNZ-1 and BNZ-2. The active metabolites 4-hydroxyalprazolam acts on these receptors with 0.20 times the potency of alprazolam and alpha-hydroxyalprazolam acts on these receptors with 0.66 times the potency.

The effect of alprazolam on BNZ-1 mediates the sedation and anti-anxiety effects of the drug while the action on BNZ-2 mediates effects on memory, coordination, muscle relaxation, and anticonvulsive activity.

Alprazolam also couple with GABA-A receptors to enhance GABA binding to its receptor. This interaction mediates inhibition of the nervous system and results in a calming effect.

The molecular mechanisms as well as the clinical effects of alprazolam have both been well demonstrated, however the means by which the molecular mechanism translates to a clinical effect is still not understood.

Propranolol is a nonselective β-adrenergic receptor antagonist. Blocking of these receptors leads to vasoconstriction, inhibition of angiogenic factors like vascular endothelial growth factor (VEGF) and basic growth factor of fibroblasts (bFGF), induction of apoptosis of endothelial cells, as well as down regulation of the renin-angiotensin-aldosterone system.

Dosage

Plxna dosage

Treatment should be initiated with a dose of 0.25 to 0.5 mg three times daily. Depending on the response, dose may

be increased at intervals of 3 to 4 days in increments of no more than 1 mg per day. The maximum dose should not

exceed 4 mg/day. Occasional patients with panic disorder may need as much as 10 mg a day to achieve a

successful response and in these cases periodic reassessment and consideration of dosage adjustment is required.

Dosage should be individualized for maximum beneficial effect with a lowest possible dose. If side-effects occur at

starting dose, dose may be lowered. When discontinuing therapy, dosage should be reduced gradually by no more

than 0.5 mg every three days.

In elderly patients or in patients with advanced liver disease, the usual starting dose is 0.25 mg, two or three times

daily and may be gradually increased if needed and tolerated. Safety and effectiveness of Alprazolam in individuals

below 18 years of age have not been established.

Alprazolam XR 1 should be administered once daily, preferably in the morning by patients who are on multiple dosage

regimen of Alprazolam 0.25/0.5 mg. The tablets should be taken intact, they should not be chewed, crushed, or broken.

Tablet:

Adults:

• Hypertension: A starting dose of 80 mg twice a day may increased at weekly intervals according to response. The usual dose range is 160-320 mg per day. With concurrent diuretic or other antihypertensive drugs a further reduction of blood pressure is obtained.
• Angina, anxiety, migraine and essential tremor: A staring dose of 40 mg two or three times daily may be increased by the same amount at weekly intervals according to patients response. An adequate response in anxiety, migraine and essential tremor is usually seen in the range 80-160 mg/day and an angina in the range 120-240 mg/day.
• Situational and generalized anxiety: A dose of 40 mg daily may provide short term relief of acute situational anxiety. Generalized anxiety require long term therapy, usually responds adequately to 40 mg twice daily which ,which individual cases, may be increased to 40 mgthree times daily. Treatment should be continued according to responses. Patients should reviewed after 6 to 12 months treatment.
• Dysrhythmias, anxiety tachycardia, hypertrophic obstructive cardiomyopathy and thyrotoxicosis: A dosage range of 10-40 mg three or four times a day usually achieves the required response.
• Post myocardial infarction: Treatment should be started between days 5 and after 21 after myocardial infarction, with an initial dose of 40 mg four times a day for 2 or 3 days. In order to improve compliance the total daily doses three after be given as 80 mg twice a day. Phaeochromocytoma (Used only with an alpha receptor blocking drug).
• Pre-operative: 60 mg daily for three days.
• Non-operable malignant cases: 30 mg daily.
• Migraine: Under 12 years: 20 mg two or three times daily.Over 12 years : The adult dose.

Children:

• Sysrhythmias, Phaeochromocytoma, Thyrotoxicisis: Dosage should be individually determined and the following is only a guide 0.25-0.5 mg/kg three or four times daily as required.

Sustained Release Capsule:

Adult:

• Hypertension: The usual initial dose is 80mg Propranolol SR once daily, whether used alone or added to a diuretic. The usual maintenance dosage is 120 to 160 mg once daily.
• Angina pectoris: Starting with 80mg Propranolol SR once daily, dosage should be gradually increased three to seven day intervals until optimum response is obtained.
• Migraine: The initial oral dose is 80 mg Propranolol SR once daily. T he usual effective dose range is 160 to 240 mg once daily. It may be advisable to withdraw the drug gradually over a period of several weeks.
• Hypertrophic subaortic stenosis: 80 mg Propranolol SR once daily

Injection:

Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.

The usual dose is 1 to 3 mg administered under careful monitoring, such as electrocardiography and central venous pressure. The rate of administration should not exceed 1 mg (1 mL) per minute to diminish the possibility of loweringblood pressureand causing cardiac standstill.

Sufficient time should be allowed for the drug to reach the site of action even when a slow circulation is present. If necessary, a second dose may be given after two minutes. Thereafter, additional drug should not be given in less than four hours. Additional propranolol hydrochloride should not be given when the desired alteration in rate or rhythm is achieved.

Transfer to oral therapy as soon as possible.

Side Effects

Side effects, if occur, are generally observed at the beginning of therapy and usually disappear upon continued medication. The most frequent side effects are drowsiness and light headedness. The other side effects, that may occur include depression, headache, confusion, dry mouth, constipation etc.

Propranolol is usually well tolerated. Minor side effects such as cold extremities, nausea, diarrhea, sleep disturbances and lassitude are often transient. There have been reports of skin rashes and/or dry eyes associated with the use of beta-adrenergic blocking drugs.

Toxicity

Alprazolam overdose can present as sleepiness, confusion, poor coordination, slow reflexes, coma, and death. Taking alprazolam with alcohol lowers the threshold for overdose. Patients should have their respiration, pulse, and blood pressure monitored. Patients can be treated by gastric lavage and intravenous fluids.. If hypotension occurs, patients may be treated with vasopressors. In known, or suspected overdoses, patients can be given the benzodiazepine receptor antagonist flumazenil in addition to other methods of management.

Oral LD50 in rats is 331-2171mg/kg.

Alprazolam is a pregnancy category D teratogen meaning there is evidence of risk to the fetus of a mother taking alprazolam but in some cases the benefit may outweigh the risk. Children born to these mothers are also at risk of withdrawal symptoms, flaccidity, and respiratory issues.

Benzodiazepines are expressed in human breast milk and so nursing is generally not recommended in mothers taking alprazolam.

Alprazolam is not associated with carcinogenicity, mutagenicity, or impairment of fertility.

Symptoms of overdose include hypotension, hypoglycemic seizure, restlessness, euphoria, insomnia. Patients with asthma may develop bronchospasm. In case of overdose, monitor vital signs, mental status, and blood glucose. Treat hypotension with intravenous fluids, bradycardia with atropine, and isoproterenol and aminophylline for bronchospasm. If patients do not respond to intravenous fluids, follow up with glucagon 50-150µg/kg intravenously, then 1-5mg/hour, followed by catecholamines. Dialysis will not be useful as propranolol is highly protein bound.

Precaution

Because Alprazolam may produce psychological and physical dependence, increment of dose or abrupt discontinuation of Alprazolam therapy should not be done without physician's advice. Duration of therapy must be determined by the physicians. Alprazolam should be administered with caution to patients with hepatic or renal disease, chronic pulmonary insufficiency or sleep apnea.

Beta-adrenoceptor blocking drugs should be avoided in over heart failure. Propranolol modifies the tachycardia of hypoglycaemic therapy in diabetic patients. Propranolol may prolong the hypoglycaemic response to insulin.

Interaction

Alprazolam produces additive CNS depressant effects when co-administered with other psychotropic medications, anticonvulsants, antihistaminics, ethanol and other drugs which themselves produce CNS depression.

Beta-adrenoceptor blocking drugs interact with clonidine.If beta-adrenoceptor blocking drugs and clonidine are given concurrently, clonidine should be discontinued until several days after withdrawal of beta-adrenoceptor blocking drug. Care should be taken in prescribing a beta-adrenoceptor blocking drugs with class 1 antidysrhythmic agents (disopyramide).Beta-adrenoceptor blocking drugs should be used with caution in combination with verapamil in patients with impaired ventricular function.

Volume of Distribution

Volume of distribution following oral administration is 0.8-1.3L/kg. Alprazolam crosses the blood-brain barrier.

The volume of distribution of propranolol is approximately 4L/kg or 320L.

Elimination Route

Oral bioavailability of a standard release tablet of alprazolam is 84-91% with a time to maximum concentration of 1.8 hours. A 1mg oral dose of alprazolam leads to a maximum plasma concentration of 12-22mcg/L. Alprazolam is rapidly absorbed in the gastrointestinal tract.

Data for the area under the curve and the effect of taking alprazolam with food are not readily available.

Patients taking doses of 40mg, 80mg, 160mg, and 320mg daily experienced C_max values of 18±15ng/mL, 52±51ng/mL, 121±98ng/mL, and 245±110ng/mL respectively. Propranolol has a T_max of approximately 2 hours, though this can range from 1 to 4 hours in fasting patients. Taking propranolol with food does not increase T_max but does increase bioavailability.

Half Life

11.2 hours in healthy patients. The half life is 16.3h in the elderly, 5.8-65.3h in patients with alcoholic liver disease, 9.9-40.4h in obese patients. The half life is 25% higher in Asian patients compared to Caucasians. Other studies have shown the half life to be 9-16h.

The elimination half life of propranolol is approximately 8 hours. The plasma half life of propranolol is 3 to 6 hours.

Clearance

Oral clearance is 0.90±0.21mL/min/kg but this increases to 2.13±0.54mL/min/kg when given with CYP3A inducers. Other studies have demonstrated a clearance of 0.70-1.5mL/min/kg.

The clearance of propranolol is 2.7±0.03L/h/kg in infants 90 days. Propranolol clearance increases linearly with hepatic blood flow. Propanolol has a clearance in hypertensive adults of 810mL/min.

Elimination Route

Alprazolam is mainly eliminated in the urine. A large portion of the dose is eliminated as unmetabolized alprazolam. 2

91% of an oral dose of propranolol is recovered as 12 metabolites in the urine.

Pregnancy & Breastfeeding use

Pregnancy: Alprazolam has been categorized in pregnancy category D; that means, it should be avoided in pregnancy.

Lactation: Like other benzodiazepines, Alprazolam is assumed to be excreted in breast milk. Therefore, nursing should not be undertaken by mothers who must use Alprazolam.

There are no adequate and controlled studies in pregnant women. Propranolol is excreted in human milk. Caution should be exercised when propranolol is administered to a nursing mother.

Contraindication

Contraindicated in patients with hypersensitivity to alprazolam or other benzodiazepines. Alprazolam is also contraindicated in patients with myasthenia gravis, acute narrow angle glaucoma, during pregnancy and also in infants.

Propranolol Hydrochloride is contraindicated in patients with known Hypersensitivity to any component of the formulation. If there is a history of bronchial asthma of bronchospasm.

Special Warning

Use in Children: Safety and efficacy of Alprazolam in patients under the age of 18 years has not been established.

Acute Overdose

Manifestations of Alprazolam over dosage include somnolence, confusion, impaired coordination, diminished reflexes and coma. In such cases of over dosage general supportive measures should be employed along with immediate gastric lavage.

The symptoms of over dosage may include bradycardia, hypotension, acute cardiac insufficiency and bronchospasm. Treatment of over dosage include close supervision, treatment in an intensive care ward, he use of gastric lavage, activated charcoal and a laxative to prevent absorption of any drug still present in the gastrointestinal tract, the use of plasma or plasma substitutes to treat hypotension and shock.

Storage Condition

Alprazolam tablets should be stored in a cool and dry place, protected from light and moisture.

Store in a cool dry place. Protect from light.

Innovators Monograph

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