Release
Ambien contains the compound zolpidem. Like all medications, zolpidem is gradually eliminated from the body. As Drugs.com indicates, the half-life of zolpidem is approximately 2 1/2 hours (it varies from patient to patient). This means that every 2 1/2 hours, half of the zolpidem in the body is metabolized. This short half-life means zolpidem doesn't cause the "hangover" feeling that other sleeping pills can cause. On the other hand, it also means that the effects of zolpidem can wear off rather quickly. Ambien CR is designed to release some zolpidem rapidly (to help the user fall asleep) and also releases more zolpidem gradually (to keep the levels constant during the night).
Neurotransmitters
Zolpidem has its sedative effects by acting on neurons in the brain. Neurons in the brain are connected with thousands of other neurons via small junctions called synapses. When one neuron wants to send a signal to the other neurons in the synapse, it releases a chemical called a neurotransmitter. Neurotransmitters bind to receptors, which are specialized proteins on the surfaces of the neurons in the synapse. The same neurotransmitter can have different effects on different neurons, depending on what receptors are present.
Zolpidem Mechanism
Zolpidem works by binding to some of the receptors for a neurotransmitter called GABA. According to HealthScout, Zzlpidem works similarly to the benzodiazepine class of medications, but it only binds to certain subtypes of the GABA receptor. GABA is a neurotransmitter that blocks the activity of other neurons. When zolpidem binds to GABA receptors, it causes inhibitory activity in the brain. This diminished neuronal activity leads to the patient falling asleep more easily, which is why zolpidem is sometimes called a hypnotic.
