XANAX XR 1 MG

Indications

• Anxiety disorders
• Panic disorder

Dosage

Children: Refer to clinical guidelines or BNF for Children for specific dosing information.

Adults: Refer to clinical guidelines or BNF for specific dosing information.

Mechanism of action

Alprazolam enhances the effect of the neurotransmitter gamma-aminobutyric acid (GABA) at the GABA-A receptor. This results in increased neuronal inhibition, leading to its anxiolytic, sedative, and muscle relaxant properties. The drug binds to specific sites on the GABA-A receptor, increasing the frequency of chloride channel opening and resulting in hyperpolarization of the neuron.

Pharmacodynamics

The pharmacodynamics of alprazolam involve its actions on the central nervous system. The drug produces anxiolytic effects by reducing the activity of the limbic system and other brain areas that regulate emotions and anxiety. It also exhibits sedative and hypnotic properties, making it effective for short-term treatment of insomnia associated with anxiety.

Pharmacokinetics

Alprazolam is well-absorbed following oral administration, with peak plasma concentrations occurring within 1-2 hours. It is extensively metabolized by the liver, primarily via cytochrome P450 3A4, into pharmacologically active metabolites. The elimination half-life ranges from 6 to 27 hours, depending on individual metabolism. Alprazolam is excreted mainly in the urine as metabolites, with a small fraction eliminated unchanged.

Contra-indications

• Hypersensitivity to alprazolam or any component of the formulation
• Acute narrow-angle glaucoma
• Severe respiratory insufficiency
• Sleep apnea syndrome
• Severe hepatic impairment
• Concurrent use with strong CYP3A4 inhibitors

Adverse effects

• Drowsiness
• Dizziness
• Fatigue
• Cognitive impairment
• Dependence and withdrawal symptoms
• Confusion
• Ataxia
• Gastrointestinal disturbances
• Mood changes
• Paradoxical reactions such as increased anxiety or agitation

Interactions

• CNS depressants (e.g., alcohol, opioids, other benzodiazepines) may enhance sedative effects
• CYP3A4 inhibitors (e.g., ketoconazole, erythromycin) may increase alprazolam levels
• CYP3A4 inducers (e.g., rifampicin, St. John's Wort) may decrease alprazolam levels
• Theophylline may reduce the effects of alprazolam
• Anticonvulsants may alter the metabolism of alprazolam

Precautions

• Use with caution in patients with a history of substance use disorder
• Monitor for signs of respiratory depression, especially in combination with other CNS depressants
• Gradual dose reduction is recommended to avoid withdrawal symptoms
• Use in elderly patients may require dose adjustment due to increased sensitivity
• Assess for underlying depression or suicidal ideation

Pregnancy

Alprazolam is categorized as a pregnancy category D medication. It is not recommended for use during pregnancy due to potential risks to the fetus, including congenital malformations and withdrawal symptoms in newborns.

Breast-feeding

Alprazolam is excreted in breast milk. Breastfeeding mothers should use caution, as there may be risks of sedation and withdrawal in the nursing infant.

Storage

Store at room temperature, away from moisture and heat. Keep out of reach of children.

Formulations

• Tablets
• Extended-release tablets
• Oral solution