Xanax is a brand name for the drug alprazolam, which belongs to a group of drugs called benzodiazepines.1
Benzodiazepines act on the brain and central nervous system to produce a calming effect.2 Xanax slows down the movement of brain chemicals that may have become unbalanced, resulting in a reduction in nervous tension and anxiety. Xanax works by boosting the effects of a natural chemical made in the brain called gamma-aminobutyric acid (GABA).
GABA is an amino acid C4H9NO2 that is a neurotransmitter, which induces inhibition of postsynaptic neurons - slows down activity of nerve cells in the brain.3
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Here are some key points about Xanax. More detail and supporting information is in the main article.
- Xanax (alprazolam) is the single most prescribed psychiatric medication in the US
- Xanax is a member of the benzodiazepine family of drugs and is primarily used to treat anxiety and panic disorders
- Xanax is dispensed in 0.25 mg, 0.5 mg, 1 mg and 2 mg strengths
- At the same dosage, the drug is 10-20 times as potent as Valium
- Xanax works by increasing the amount of the neurotransmitter GABA in the brain to promote calmness and a relaxed feeling
- The short half-life and its quick acting effect - sometimes within minutes - make Xanax so addictive
- Abrupt discontinuation of Xanax is never recommended; the early stage of withdrawal symptoms is accompanied by a sense of anxiety and apprehension coupled with tremors and headache
- Overdoses of Xanax can be mild to severe depending on how much of the drug is taken and if any other medications are involved
- Combined overdose with antidepressants, alcohol or opiates significantly increases the likelihood for severe toxicity and possible fatality
- When taken correctly, Xanax is a safe and effective medication.
What is Xanax?
Alprazolam is an anti-anxiety medication in the benzodiazepine family, the same family that includes diazepam (Valium), clonazepam (Klonopin), lorazepam (Ativan), flurazepam (Dalmane), and others.9 Xanax works by decreasing abnormal excitement in the brain.11
The FDA approved alprazolam in October 1981.
Commonly used brand names
Brands of alprazolam include:1,11,13
- Xanax tablets: 0.25 mg, 0.5 mg, 1 mg, 2 mg
- Xanax XR extended release tablets: 0.5 mg, 1 mg, 2 mg, 3 mg
- Niravam orally disintegrating tablets: 0.25 mg, 0.5 mg, 1 mg, 2 mg
- Alprazolam Intensol liquid (concentrate): 1 mg/ml.
Important information about Xanax
Xanax are dispensed in 0.25 mg, 0.5 mg, 1 mg and 2 mg strengths.
For all users of Xanax:4
To ensure safe and effective use of benzodiazepines, all patients prescribed with Xanax should be provided with the following guidance:
- Inform your physician about any alcohol consumption and medicine you are currently taking, including medication you may buy without a prescription. Alcohol should generally not be used during treatment with benzodiazepines
- Xanax is not recommended for use in pregnancy. Inform your physician if you are pregnant, if you are planning to have a child, or if you become pregnant while you are taking this medication
- Inform your physician if you are nursing
- Until you experience how Xanax affects you, do not drive a car or operate potentially dangerous machinery
- Do not increase the dose of Xanax even if you think the medication "does not work anymore" without consulting your physician. Benzodiazepines, even when used as recommended, may produce emotional and physical dependence
- Do not stop taking Xanax abruptly or decrease the dose without consulting your physician, since withdrawal symptoms can occur.
Inform your doctor if you have asthma or other breathing problems, glaucoma, kidney or liver diseases, history of alcoholism or depression, suicidal thoughts or an addiction to drugs or alcohol.
You should not take Xanax if you:
- Have narrow-angle glaucoma
- Are also taking itraconazole (Sporanox) or ketoconazole (Nizoral)
- Are allergic to alprazolam or to other benzodiazepines, such as chlordiazepoxide (Librium), clorazepate (Tranxene), diazepam (Valium), lorazepam (Ativan) or oxazepam (Serax).
Xanax is a federally controlled substance because it has abuse potential.8
Xanax is often abused for the fast-acting, relaxed "high" it can give to people who take it, including people without a prescription.10
According to the National Institute on Drug Abuse (NIDA), benzodiazepines such as Xanax were responsible for most of the emergency room visits attributed to central-nervous-system depressants in 2009.
According to the Substance Abuse and Mental Health Services Administration, in 2011, there were over 1.2 million emergency department visits overall related to the nonmedical use of prescription drugs - alprazolam was involved in 10% of those visits.12
Alprazolam was the 13th most commonly sold medication in 2012 and was the psychiatric medication most commonly prescribed in 2011.
The number of emergency department visits involving the non-medical use of the sedative alprazolam doubled from 57,419 to 124,902 during the years 2005 to 2010, and then remained stable at 123,744 in 2011.
The most common drug combinations encountered in ER patients are Xanax and alcohol, and Xanax combined with prescription opiates like hydrocodone and oxycodone.
According to the SAMHSA report, in 81% of cases, alprazolam was mixed with another drug (including alcohol).
What does Xanax treat?
Xanax is indicated for the management of anxiety disorder or the short-term relief of symptoms of anxiety. Anxiety or tension associated with the stress of everyday life usually does not require treatment with an anxiolytic (a type of prescription medication used to treat symptoms of acute anxiety).4
Xanax is used to treat anxiety disorder and alleviate the symptoms of panic disorders.
Generalized anxiety disorder is characterized by unrealistic or excessive anxiety and worry about two or more life circumstances, for a period of 6 months or longer, during which the person has been bothered more days than not by these concerns.4
At least six of the following symptoms are often present in these patients:4
- Motor tension: trembling, twitching, feeling shaky, muscle tension, aches or soreness, restlessness, easy fatigability
- Autonomic hyperactivity: shortness of breath or smothering sensations, palpitations or accelerated heart rate, sweating, or cold clammy hands, dry mouth, dizziness or light-headedness, nausea, diarrhea, or other abdominal distress, flushes or chills, frequent urination, trouble swallowing or "lump in throat"
- Vigilance and scanning: feeling keyed up or on edge, exaggerated startle response, difficulty concentrating or "mind going blank" because of anxiety, trouble falling or staying asleep, irritability.
These symptoms must not be secondary to another psychiatric disorder or caused by some organic factor.4
Panic disorder (DSM-IV) is characterized by recurrent unexpected panic attacks, i.e., a discrete period of intense fear or discomfort in which four or more of the following symptoms develop abruptly and reach a peak within 10 minutes:4
- Palpitations, pounding heart or accelerated heart rate
- Trembling or shaking
- Sensations of shortness of breath or smothering
- Feeling of choking
- Chest pain or discomfort
- Nausea or abdominal distress
- Feeling dizzy, unsteady, lightheaded or faint
- Derealization (feelings of unreality) or depersonalization (being detached from oneself)
- Fear of losing control
- Fear of dying
- Paresthesia (numbness or tingling sensations)
- Chills or hot flushes.
Side effects of Xanax
Side effects are often observed at the beginning of therapy and usually disappear upon continued use of medication. Possible side effects of Xanax include:4,6
- Low energy
- Impaired coordination
- Memory impairment
- Abnormal involuntary movement
- Decreased libido
- Confusional state
- Muscle twitching
- Muscle cramps
- Increased libido
- Dry mouth
- Increased salivation
- Inflammation of skin caused by allergy
- Chest pain
- Nasal congestion
- Blurred vision
- Menstrual disorders
- Upper respiratory infection
- Dream abnormalities
- Increased appetite
- Weight gain
- Decreased appetite
- Weight loss
- Slurred speech
Xanax may cause drowsiness, dizziness, light-headedness or blurred vision. Do not drive, operate machinery, or do anything else that could be dangerous until you know how you react to Xanax.
The above is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. Side effects can be reported to the FDA at 1-800-FDA-1088.
Seek emergency medical help if you have any of these signs of an allergic reaction to Xanax: hives, difficulty breathing, and swelling of your face, lips, tongue or throat.5
Call your doctor at once if you have a serious side effect such as:
- Depressed mood, thoughts of suicide or hurting yourself, unusual risk-taking behavior, decreased inhibitions, no fear of danger
- Confusion, hyperactivity, agitation, hostility, hallucinations
- Feeling like you might pass out
- Urinating less than usual or not at all
- Chest pain, pounding heartbeats or fluttering in your chest
- Uncontrolled muscle movements, tremor, seizure (convulsions)
- Jaundice (yellowing of the skin or eyes).
How to use Xanax
Alprazolam comes as a tablet, an extended-release tablet, an orally disintegrating tablet (tablet that dissolves quickly in the mouth), and a concentrated solution (liquid) to take by mouth.11
Xanax should be taken by mouth as directed by your doctor. Dosage is based on the following factors:2
- Medical condition
- Response to treatment.
Dosage of Xanax may be increased gradually until the drug works effectively for the patient. The instructions of a doctor should be closely followed to reduce the risk of side effects.
If this medication has regularly been used for a long time or in high doses, withdrawal symptoms (such as seizures) can occur if usage is suddenly stopped. To prevent these reactions, the doctor may reduce the dosage of Xanax gradually.
Xanax are available in doses of:
- 0.25 mg - white, oval, scored, imprinted "XANAX 0.25"
- 0.5 mg - peach, oval, scored, imprinted "XANAX 0.5"
- 1 mg - blue, oval, scored, imprinted "XANAX 1.0"
- 2 mg - white, oblong, multi-scored, imprinted "XANAX" on one side and "2" on the reverse side.
Do not crush, chew or break a Xanax extended-release tablet. Swallow the tablet whole. It is specially made to release medicine slowly in the body. Breaking the tablet would cause too much of the drug to be released at one time.5
Do not share your medicine with other people. It may not be suitable for them and may harm them.
What happens if I miss a dose?
If you miss a dose of Xanax, take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.5
What happens if I overdose?
Manifestations of an alprazolam overdose include somnolence, confusion, impaired coordination, diminished reflexes, and coma. Death has been reported in association with overdoses of alprazolam by itself, as it has with other benzodiazepines.4
If an overdose of Xanax occurs, call your doctor or 911. Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.5
Xanax should be stored at controlled room temperature 20° to 25°C.
Changes in the absorption, distribution, metabolism and excretion of benzodiazepines have been reported in a variety of states and populations such as:4
- Alcoholic liver disease
- Impaired hepatic function
- Impaired renal function
- Elderly patients
- Obese patients.
Do not use Xanax if you are allergic to alprazolam or other benzodiazepines such as chlordiazepoxide (Librium), clorazepate (Tranxene), diazepam (Valium), lorazepam (Ativan), or oxazepam (Serax).5
Do not drink alcohol while taking Xanax. Xanax can increase the effects of alcohol.5
Xanax is in FDA pregnancy category D. Do not use Xanax if you are pregnant. Benzodiazepines can potentially cause fetal harm when administered to pregnant women. Xanax is assumed to be like other members of the benzodiazepine class and are capable of causing an increased risk of congenital abnormalities when administered to a pregnant woman during the first trimester.
Benzodiazepines, including Xanax, can potentially cause fetal harm when administered to pregnant women.
Use of Xanax during the first trimester of pregnancy should usually be avoided.
Patients should be advised that if they become pregnant during therapy or intend to become pregnant they should communicate with their physicians about the desirability of discontinuing the drug.4
The child born of a mother who is receiving benzodiazepines may be at some risk for withdrawal symptoms from the drug during the postnatal period. Also, respiratory problems have been reported in children born to mothers who have been receiving benzodiazepines.4
Due alprazolam's similarity to other benzodiazepines, it is assumed that Xanax undergoes transplacental passage and that it is excreted in human milk.4
Chronic administration of diazepam (another benzodiazepine) to nursing mothers has been reported to cause their infants to become lethargic and to lose weight. As a general rule, mothers who must use Xanax should not undertake nursing.4
Alprazolam has not been studied in pediatric patients.4 Safety and effectiveness of Xanax in individuals below 18 years of age has not been established.
Gender has no effect on pharmacokinetics (the process by which a drug is absorbed, distributed, metabolized and eliminated by the body) of alprazolam.4
The elderly may be more sensitive to the effects of benzodiazepines. They exhibit higher plasma alprazolam concentrations due to reduced clearance of the drug as compared with a younger population receiving the same doses.4
The sedative effects of Xanax may last longer in older adults. Accidental falls are common in elderly patients who take benzodiazepines. Use caution to avoid falling or accidental injury while you are taking Xanax.5
Maximal concentrations (the peak concentration that a drug achieves in a specified compartment after the drug has been administrated and before administration of a second dose) and half-life (the time required for the concentration of the drug to reach half of its original value) are approximately 15% and 25% higher in Asian populations compared with white populations.4
Alprazolam concentrations may be reduced up to 50% in smokers compared to non-smokers.4
As with other psychotropic medications, the usual precautions with respect to administration of the drug and size of the prescription are indicated for severely depressed patients or those in whom there is reason to expect concealed suicidal ideation or plans. Panic disorder has been associated with primary and secondary major depressive disorders and increased reports of suicide among untreated patients.4
Episodes of hypomania and mania have been reported in association with the use of Xanax in patients with depression.4
Uricosuric effect (promoting the excretion of uric acid in the urine)
Alprazolam has a weak uricosuric effect. Although other medications with weak uricosuric effect have been reported to cause acute renal failure, there have been no reported instances of acute renal failure attributable to therapy with Xanax.
Alprazolam is primarily eliminated from the body by metabolism via cytochrome P450 3A (CYP3A). Most of the interactions that have been documented with alprazolam are with drugs that inhibit or induce CYP3A4. CYP3A4 is an important enzyme in the body, mainly found in the liver and the intestine. Its purpose is to oxidize small foreign organic molecules (xenobiotics), such as toxins or drugs so that they can be removed from the body.
Potent inhibitors of CYP3A may increase plasma concentrations of alprazolam. Drugs that have this effect include:
- Cimetidine (Tagamet)
- HIV protease inhibitors, e.g., ritonavir.
Benzodiazepines, including alprazolam, produce additive CNS depressant effects when co-administered with:
- Other psychotropic medications
- Other drugs that produce CNS depression.
Other drug interactions include:
- Digoxin - increased digoxin concentrations have been reported when alprazolam was given, especially in elderly older than 65 years of age
- Imipramine and desipramine - increased plasma concentrations of imipramine and desipramine by 31% and 20% respectively
- Fluoxetine - coadministration of fluoxetine with alprazolam increased the maximum plasma concentration of alprazolam by 46%, decreased clearance by 21%, increased half-life by 17%
- Propoxyphene - coadministration of propoxyphene decreased the maximum plasma concentration of alprazolam by 6%, decreased clearance by 38%, and increased half-life by 58%
- Birth control pills - coadministration of oral contraceptives increased the maximum plasma concentration of alprazolam by 18%, decreased clearance by 22%, and increased half-life by 29%.
Studies of benzodiazepines other than alprazolam suggest a possible drug interaction with alprazolam for the following:
- Antibiotics such as clarithromycin (Biaxin), erythromycin (EES, EryPed, Ery-Tab, Erythrocin, Pediazole), rifabutin (Mycobutin), rifampin (Rifadin, Rifater, Rifamate), rifapentine (Priftin), or telithromycin (Ketek)
- Grapefruit juice
- Ergotamine (Cafergot, Ergomar, Migergot)
- Cyclosporine (Gengraf, Neoral, Sandimmune)
- Heart or blood pressure medication such as amiodarone (Cordarone, Pacerone), diltiazem (Tiazac, Cartia, Cardizem), nicardipine (Cardene), nifedipine (Nifedical, Procardia), or quinidine (Quin-G)
- Dexamethasone (Cortastat, Dexasone, Solurex, DexPak)
- Imatinib (Gleevec)
- St. John's wort
- Antifungal medication such as miconazole (Oravig) or voriconazole (Vfend)
- Antidepressants such as fluoxetine (Prozac, Sarafem, Symbyax), fluvoxamine (Luvox), desipramine (Norpramin), imipramine (Janimine, Tofranil), or nefazodone
- A barbiturate such as butabarbital (Butisol), secobarbital (Seconal), pentobarbital (Nembutal), or phenobarbital (Solfoton)
- Seizure medications such as carbamazepine (Carbatrol, Equetro, Tegretol), felbamate (Felbatol), oxcarbazepine (Trileptal), phenytoin (Dilantin), or primidone (Mysoline).
This list is not complete, and other drugs may interact with Xanax. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin and herbal products.
Do not start a new medication without telling your doctor.
Xanax dependence and withdrawal
It is important to taper off Xanax gradually; otherwise there is a risk of benzodiazepine withdrawal syndrome.
To discontinue treatment of Xanax patient dosage should be reduced and tapered slowly. Because of the danger of withdrawal, abrupt discontinuation of treatment should be avoided. It is suggested that the daily dosage of Xanax be decreased by no more than 0.5 mg every three days. Reported withdrawal symptoms of discontinuation of Xanax include:4
Withdrawal symptoms may be experienced when Xanax is discontinued. These symptoms may include insomnia, light-headedness, anxiety, fatigue and headaches.
- Fatigue and tiredness
- Abnormal involuntary movement
- Weight loss
- Decreased appetite
- Decreased salivation
- Cognitive disorder
- Blurred vision
- Muscular twitching
- Impaired coordination
- Muscle tone disorders
- Memory impairment
- Confusional state.
Alprazolam is a safe and effective medication when used as directed.13