Ambien - General Information
Ambien is a prescription short-acting nonbenzodiazepine hypnotic that potentiates gamma-aminobutyric acid (GABA), an inhibitory neurotransmitter, by binding to benzodiazepine receptors which are located on the gamma-aminobutyric acid receptors. Ambien is used for the short-term treatment of insomnia. It works quickly (usually within 15 minutes) and has a short half-life (2-3 hours). It is classified as an imidazopyridine. As an anticonvulsant and muscle relaxant, the beneficial effects start to emerge at 10 and 20 times the dose required for sedation, respectively. For that reason, it has never been approved for either muscle relaxation or seizure prevention. Recently, zolpidem has been cited in various medical reports mainly in the United Kingdom as waking persistent vegetative state (PVS) patients, and dramatically improving the conditions of people with brain injuries. [Wikipedia]
Pharmacology of Ambien
Ambien is a sedative or hypnotic agent with a chemical structure unrelated to benzodiazepines, barbiturates, or other drugs with known hypnotic properties. It interacts with a GABA-BZ receptor complex and shares some of the pharmacological properties of the benzodiazepines. In contrast to the benzodiazepines, which non-selectively bind to and activate all three alpha receptor subtypes, zolpidem in vitro binds the (alpha1) receptor preferentially. The (alpha1) receptor is found primarily on the Lamina IV of the sensorimotor cortical regions, substantia nigra (pars reticulata), cerebellum molecular layer, olfactory bulb, ventral thalamic complex, pons, inferior colliculus, and globus pallidus.
Ambien for patients
PATIENT PACKAGE INSERT
Your doctor has prescribed zolpidem tartrate to help you sleep. The following information is intended to guide you in the safe use of this medicine. It is not meant to take the place of your doctor's instructions. If you have any questions about zolpidem tartrate tablets be sure to ask your doctor or pharmacist.
Zolpidem tartrate is used to treat different types of sleep problems, such as:
- Trouble falling asleep.
- Waking up too early in the morning.
- Waking up often in the night.
Some people may have more than one of these problems.
Zolpidem tartrate belongs to a group of medicines known as the "sedative/hypnotics," or simply, sleep medicines. There are many different sleep medicines available to help people sleep better. Sleep problems are usually temporary, requiring treatment for only a short time, usually 1 or 2 days up to 1 or 2 weeks. Some people have chronic sleep problems that may require more prolonged use of sleep medicine. However, you should not use these medicines for long periods without talking to your doctor about the risks and benefits of prolonged use.
Most Common Side Effects: All medicines have side effects. Most common side effects of sleep medicines include:
- Difficulty with coordination.
You may find that these medicines make you sleepy during the day. How drowsy you feel depends upon how your body reacts to the medicine, which sleep medicine you are taking, and how large a dose your doctor has prescribed. Daytime drowsiness is best avoided by taking the lowest dose possible that will still help you sleep at night. Your doctor will work with you to find the dose of zolpidem tartrate that is best for you.
To manage these side effects while you are taking this medicine:
- When you first start taking zolpidem tartrate or any other sleep medicine until you know whether the medicine will still have some carryover effect in you the next day, use extreme care while doing anything that requires complete alertness, such as driving a car, operating machinery, or piloting an aircraft.
- NEVER drink alcohol while you are being treated with zolpidem tartrate or any sleep medicine. Alcohol can increase the side effects of zolpidem tartrate or any other sleep medicine.
- Do not take any other medicine without asking your doctor first. This includes medicines you can buy without a prescription. Some medicines can cause drowsiness and are best avoided while taking zolpidem tartrate.
- Always take the exact dose of zolpidem tartrate prescribed by your doctor. Never change your dose without talking to your doctor first.
There are some special problems that may occur while taking sleep medicines.
Memory Problems: Sleep medicines may cause a special type of memory loss or "amnesia." When this occurs, a person may not remember what has happened for several hours after taking this medicine. This is usually not a problem since most people fall asleep after taking the medicine.
Memory loss can be a problem, however, when sleep medicines are taken while traveling, such as during an airplane flight and the person wakes up before the effect of the medicine is gone. This has been called "traveler's amnesia."
Memory problems are not common while taking zolpidem tartrate. In most instances memory problems can be avoided if you take zolpidem tartrate only when you are able to get a full night's sleep (7 to 8 hours) before you need to be active again. Be sure to talk to your doctor if you think that you are having memory problems.
Tolerance: When sleep medicines are used every night for more than a few weeks, they may lose their effectiveness to help you sleep. This is known as "tolerance." Sleep medicines should, in most cases, be used only for short periods of time, such as 1 or 2 days and generally no longer than 1 or 2 weeks. If your sleep problems continue, consult your doctor, who will determine whether other measures are needed to overcome your sleep problems.
Dependence: Sleep medicines can cause dependence, especially when these medicines are used, regularly for longer than a few weeks or at high doses. Some people develop a need to continue taking their medicines. This is known as dependence or "addiction."
When people develop dependence, they may have difficulty stopping the sleep medicine. If the medicine is suddenly stopped, the body is not able to function normally and unpleasant symptoms may occur. They may find they have to keep taking the medicine either at the prescribed dose or at increasing doses just to avoid withdrawal symptoms.
All people taking sleep medicines have some risk of becoming dependent on the medicine. However, people who have been dependent on alcohol or other drugs in the past may have a higher chance of becoming addicted to sleep medicines. This possibility must be considered before using these medicines for more than a few weeks.
If you have been addicted to alcohol or drugs in the past, it is important to tell your doctor before starting zolpidem tartrate or any sleep medicine.
Withdrawal: Withdrawal symptoms may occur when sleep medicines are stopped suddenly after being used daily for a long time. In some cases, these symptoms can occur even if the medicine has been used for only a week or two.
In mild cases, withdrawal symptoms may include unpleasant feelings. In more severe cases, abdominal and muscle cramps, vomiting, sweating, shakiness, and rarely, seizures may occur. These more severe withdrawal symptoms are very uncommon.
Another problem that may occur when sleep medicines are stopped is known as "rebound insomnia." This means that a person may have more trouble sleeping in the first few nights after the medicine is stopped than before starting the medicine. If you should experience rebound insomnia, do not get discouraged. This problem usually goes away on its own after 1 or 2 nights.
If you have been taking zolpidem tartrate or any other sleep medicine for more than 1 or 2 weeks, do not stop taking it on your own. Always follow your doctor's directions.
Change In Behavior And Thinking: Some people using sleep medicines have experienced unusual changes in their thinking and/or behavior. These effects are not common. However, they have included:
- More outgoing or aggressive behavior than normal.
- Loss of personal identity.
- Strange behavior.
- Worsening of depression.
- Suicidal thoughts.
How often these effects occur depends on several factors, such as a person's general health, the use of other medicines, and which sleep medicine is being used. Clinical experience with zolpidem tartrate suggests that it is uncommonly associated with these behavior changes.
It is also important to realize that it is rarely clear whether these behavior changes are caused by the medicine, an illness, or occur on their own. In fact, sleep problems that do not improve may be due to illnesses that were present before the medicine was used. If you or your family notice any changes in your behavior, or if you have any unusual or disturbing thoughts, call you doctor immediately.
Sleep medicines may cause sedation of the unborn baby when used during the last weeks of pregnancy.
Be sure to tell your doctor if you are pregnant, if you are planning to become pregnant, or if you become pregnant while taking zolpidem tartrate.
Safe Use of Sleeping Medicines
To ensure the safe and effective use of zolpidem tartrate or any other sleep medicine, you should observe the following cautions:
1. Zolpidem tartrate is a prescription medicine and should be used only as directed by your doctor. Follow your doctor's instructions about how to take, when to take, and how long to take zolpidem tartrate.
2. Never use zolpidem tartrate or any other sleep medicine for longer than directed by your doctor.
3. If you notice any unusual and/or disturbing thoughts or behavior during treatment with zolpidem tartrate or any other sleep medicine, contact your doctor.
4. Tell your doctor about any medicine you may be taking, including medicines you may buy without a prescription. You should also tell your doctor if you drink alcohol. DO NOT use alcohol while taking zolpidem tartrate or any other sleep medicine.
5. Do not take zolpidem tartrate or any other sleep medicine unless you are able to get a full night's sleep before you must be active again. For example, zolpidem tartrate or any other sleep medicine should not be taken on an overnight plane flight of less than 7 or 8 hours since "traveler's amnesia" may occur.
6. Do not increase the prescribed dose of zolpidem tartrate or any other sleep medication unless instructed by your doctor.
7. When you first start taking zolpidem tartrate or any other sleep medicine until you know whether the medicine will still have some carryover effect in you the next day, use extreme care while doing anything that requires complete alertness, such as driving a car, operating machinery, or piloting an aircraft.
8. Be aware that you may have more sleeping problems the first night or two after stopping zolpidem tartrate or any other sleep medicine.
9. Be sure to tell your doctor if you are pregnant,if you are planning to become pregnant, or if you become pregnant while taking zolpidem tartrate.
10. As with all prescription medicines, never share zolpidem tartrate or any other sleep medicines with anyone else. Always store zolpidem tartrate or any other sleep medicine in the original container out of reach of children.
11. Zolpidem tartrate works very quickly. You should only take zolpidem tartrate right before going to bed and are ready to go to sleep.
Zolpidem tartrate was evaluated in healthy volunteers in single-dose interaction studies for several CNS drugs. A study involving haloperidol and zolpidem revealed no effect of haloperidol on the pharmacokinetics or pharmacodynamics of zolpidem. Imipramine in combination with zolpidem produced no pharmacokinetic interaction other a 20% decrease in peak levels of imipramine, but there was an additive effect of decreased alertness. Similarly, chlorpromazine in combination with zolpidem produced no pharmacokinetic interaction, but there was an additive effect of decreased alertness and psychomotor performance. The lack of a drug interaction following single-dose administration does not predict a lack following chronic administration.
An additive effect on psychomotor performance between alcohol and zolpidem was demonstrated.
A single-dose interaction study with zolpidem 10 mg and fluoxetine 20 mg at steady-state levels in male volunteers did not demonstrate any clinically significant pharmacokinetic or pharmacodynamic interactions. When multiple doses of zolpidem and fluoxetine at steady-state concentrations were evaluated in healthy females, the only significant change was a 17% increase in the zolpidem half-life. There was no evidence of an additive effect in psychomotor performance.
Following five consecutive nightly doses of zolpidem 10 mg in the presence of sertraline 50 mg (17 consecutive daily doses, at 7:00 am, in healthy female volunteers), zolpidem C max was significantly higher (43%) and T max was significantly decreased (53%). Pharmacokinetics of sertraline and N-desmethylsertraline were unaffected by zolpidem.
Since the systemic evaluation of zolpidem tartrate in combination with other CNS-Active drugs have been limited, careful consideration should be given to the pharmacology of any CNS-Active drug to be used with zolpidem. Any drug with CNS-depressant effects could potentially enhance the CNS- depressant effects of zolpidem.
Drugs that affect drug metabolism via cytochrome P450: A randomized, double-blind, crossover interaction study in ten healthy volunteers between itraconazole (200 mg once daily for 4 days) and a single dose of zolpidem (10 mg) given 5 hours after the last dose of itraconazole resulted in a 34% increase in AUC0->∞ of zolpidem. There were no significant pharmacodynamic effects of zolpidem on subjective drowsiness, postural sway, or psychomotor performance.
A randomized, placebo-controlled, crossover interaction study in eight healthy female volunteers between 5 consecutive daily doses of rifampin (600 mg) and a single dose of zolpidem (20 mg) given 17 hours after the last dose of rifampin showed significant reductions of the AUC (ñ73%), Cmax (ñ58%), and T1/2 (ñ36%) of zolpidem together with significant reductions in the pharmacodynamic effects of zolpidem.
A study involving cimetidine/zolpidem and ranitidine/zolpidem combinations revealed no effect of either drug on the pharmacokinetics or pharmacodynamics of zolpidem. Zolpidem had no effect on digoxin kinetics and did not effect prothrombin time when given with warfarin in normal subjects. Zolpidem's sedative/hypnotic effect was reversed by flumazenil; however, no significant alterations in zolpidem pharmacokinetics were found.
Additional information about Ambien
Ambien Indication: For the short-term treatment of insomnia.
Mechanism Of Action: Ambien modulates the alpha-subunit, known as the benzodiazepine receptor, within the GABAA receptor chloride channel macromolecular complex. Unlike the benzodiazepines, which non-selectively interact with all three alpha-receptor subtypes, Ambien preferentially binds to the alpha-1 receptor.
Drug Interactions: Not Available
Food Interactions: Avoid alcohol.
Take 30-60 minutes before breakfast.
Generic Name: Zolpidem
Synonyms: Zolpidemum [Latin]; Zolpidem tartrate
Drug Category: Hypnotics and Sedatives
Drug Type: Small Molecule; Approved
Other Brand Names containing Zolpidem: Ambien; Ivadal; Lorex; Niotal; Stilnoct; Stilnox;
Absorption: Zolpidem is rapidly absorbed from the GI tract.
Toxicity (Overdose): Oral (male rat) LD50 = 695 mg/kg. Symptoms of overdose include impairment of consciousness ranging from somnolence to light coma.
Protein Binding: 92.5 ± 0.1% (independent of concentration between 40 and 790 ng/mL)
Biotransformation: Zolpidem is converted to inactive metabolites in the liver.
Half Life: 2.6 hours
Dosage Forms of Ambien: Tablet Oral
Chemical IUPAC Name: N,N-dimethyl-2-[6-methyl-2-(4-methylphenyl)imidazo[3,2-a]pyridin-3-yl]acetamide
Chemical Formula: C19H21N3O
Zolpidem on Wikipedia: http://en.wikipedia.org/wiki/Zolpidem
Organisms Affected: Humans and other mammals