Structural Biochemistry/Prozac

Introduction

Prozac, also known as Fluoxetine, is part of class of drugs known as selective serotonin reuptake inhibitors, or SSRIs, that is used to treat depression, obsessive-compulsive disorder, eating disorders, and panic attacks. The medicine works by maintaining the levels of serotonin, a neurotransmitter that controls mood and mental state, in the brain. In other cases, Prozac is used to treat alcoholism, attention-deficit disorder, borderline personality disorder, sleeping disorders, heaches, mental illnesses, post-traumatic stress disorder, Tourettes' syndrome, obesity, sexual disorders, and various irrational fears

Side Effects

Some common side effects of Prozac are depression, anxiety, headaches, nausea, diarrhea, insomnia, and loss of appetite. Due to how Fluoxetine effects neurotransmitters, it can sometimes block other neurotransmitters like for acetylcholine. When Acetylcholine is blocked, nausea occurs. Another dangerous side effect is the fact that selective serotonin reuptake inhibitors also inhibit nitric oxide synthesis which leads to the narrowing of blood vessels. This is dangerous because it can lead to hypertension. Also, even though Prozac is an antidepressant drug it can lead to depression due to the neurological chemical imbalance in the brain.

Administration

Prozac is administered orally. A capsule is taken and slowly distributed while in the digestive system.

Precautions

Prozac should never be taken more than prescribed. A major imbalance to the neurotransmitters and neurological pathways would occur and lead to many side effects. It should not be taken while pregnant, due to the fact of hypertension, which will lead to heart defects and lung problems in the newborn. Also, Prozac should not be taken in combination of other antidepressants because of seriously dangerous chemical reactions. Lastly, people under 24 years old may have thoughts of suicide.

Biochemistry

The way Prozac works is by blocking the signal on the axon that tells it when enough serotonin has been produced. Therefore, an excess amount of serotonin is delivered to the nerves. The way Fluoxetine is metabolized is by CYP2D6 in the liver. Due to its slow metabolism, it has a long half-life within the system. Because of this slow accumulation, it takes a while before the excess serotonin starts to show significant effects. Prozac acts as an agonist for 5HT2C receptors which have been known to be responsible for the defensive and aggressive behavior. It has been seen that low 5-HT levels in the brain have traditionally been associated with depression.

Mechanism of Actions

Neurotransmitters are signaling molecules that are used to transmit messages between neurons in the brain. The pathways of neurotransmitters in the synapse can be prolonged or shortened by specific chemicals called neuromodulators. Some neuromodulators can aid with the release of neurotransmitters into the synapse; others inhibit the reabsorption of neurotransmitters by neurons so that the neurotransmitters remain in the synapse. Under certain mental conditions such as bipolar disorder, obsessive-compulsive disorder, anxiety, and depression, the regulation of secretion and removal of neurotransmitters into the synapse is not functioning properly. In particular, in depression and similar disorders, neurotransmitter seretonin is one of the mostly affected. To treat depression, the most common form of drugs is called selective serotonin reuptake inhibitors (SSRI). Prozac is one of the most widely used member of this class.

Prozac works on the serotonin balance in the synapses by inhibiting a neuromdulator called SERT, which pumps serotonin back into the neurons. Thus, Prozac helps to prevent the reabsorption of serotonin and increase the amount of seretonin in the synapse. The proper amount of seratonin in the synapse is believed to help with mood elevation and depression.

History

Eli Lilly discovered fluoxetine in the 1970's when working with antihistamine diphenhydramines. She wanted to synthesize many derivatives of this compound and test them on mice. Eventually, she made a derivative only inhibiting serotonin reuptake, which she called Prozac. Many controversial accounts have been made against Prozac and Lilly. Violent outbreaks, suicides, and murders were all thought to be seen as behavior invoked by the drug. However, it has been said that Prozac is not addictive or habit forming. Once Prozac's patent had expired in 2001, many generic serotonin inhibitor drugs started selling.

References

Johnson , George. "Smoking and drug addiction." Backgrounders. N.p.. Web. 7 December 2012.
Reichstetter, Sandra. "How Prozac works." Brain Blogger. N.p., 19 2010. Web. 7 December 2012.