THE EFFECT OF PROZAC ON THE BRAIN
Editor's Note: Copeland M. ('15) wrote this paper for her AP biology class
Introduction
In the early ‘70s it was discovered that serotonin plays a role in depression and the hypothesis that increasing 5-HT neurotransmission would be a way to help combat depression became accepted. This lead to the development of selective serotonin-reuptake inhibitor fluoxetine, which is also known as Prozac, and was approved to treat depression in 1987.
Background
Prozac is a selective serotonin reuptake inhibitor antidepressant (SSRI). Serotonin is a neurotransmitter, which means it relays signals between cells in a brain. Commonly known as fluoxetine, Prozac is one of the most popular antidepressants and is ingested by the mouth, usually once a day in the morning.
Uses
Prozac is used to treat depression, bulimia, OCD, panic disorder and premenstrual dysphoric disorder. It can be used with other medications such as olanzapine (Zyprexa) to treat depression caused by bipolar disorder. About 50% of people treating their depression with an antidepressant find that their symptoms have been greatly minimized. However, Prozac can’t be used if certain other drugs are in use because a dangerous drug interaction may occur. For example, if a patient has taken an MAO inhibitor (including isocarboxazid, linezolid, phenelzine, rasagiline, selegiline and tranycypomine) in the last fourteen days, he/she is not allowed to use Prozac or must wait five weeks after stopping Prozac before taking an MAO inhibitor.
Prozac is sometimes prescribed to people who are sick and subsequently depressed. For example, cancer patients who develop major depression are often given Prozac.
How it Works
Prozac works by blocking the absorption of serotonin in the brain. The regulation of serotonin in the brain results in a more enhanced and stable mood because the regulation makes it easier for brain cells to communicate messages to each other. Also, SSRIs increase the amount of serotonin in the brain, which is another reason Prozac is thought to better the symptoms of depression.
Recent research suggests that antidepressants like Prozac don’t treat depression by altering the chemical imbalances in the brain, but rather that depression kills neurons in the brain while Prozac stimulates the growth of neurons.
SSRIs such as Prozac work by inhibiting SERT, a transporter, which pumps serotonin into the neurons. This shortens the time that serotonin has to deliver its signal, which increases serotonin function. Prozac also increases the amount of serotonin in the synaptic gap (the space between the neurons). The increased concentration of serotonin doesn’t give an explanation of how exactly SSRIs inhibit SERT and researchers are particularly puzzled by why it take weeks before SSRIs are fully active.
Side Effects
Although Prozac is used to treat depression, some people have suicidal thoughts when they first begin using it. This is mostly common in young people and there have been many instances of teenagers committing suicide where Prozac has thought to have triggered it.
If a pregnant woman takes Prozac, it may cause serious complications in the baby. Studies have shown that children exposed to antidepressants in the womb have worse motor development, lung problems, and a higher risk of birth defects.
To avoid side effects, a doctor may start the patient on a low dosage and gradually increase it. Similarly, side effects can become worse when one suddenly stops taking Prozac so the dosage will need to gradually decrease to avoid that.
Research
A University of Helsinki’s Neuroscience Center research project shows the affect of Prozac on a mouse’s brain. They put adult mice in a cage and repeatedly played a tone right before giving them an electric shock. They then moved the mice to a different cage where the same tone played but no electric shock followed. Previous research has shown that mice less than three weeks old quickly learn that the tone no longer means that a shock is coming but adults are unable to learn that and always fear what will happen after the tone. But, when the adult mice are given Prozac they’re able to learn that the tone no longer means a shock is coming. They found that Prozac minimizes fear in mice by increasing brain plasticity.
Alternatively, separate research found that fish swimming in water with Prozac in it had negative behavioral changes. They found that Prozac can alter the genes that control their behavior and made them anxious, anti-social, and homicidal. Male fish that were exposed to Prozac ignored female fish and females produced fewer eggs. They discovered that these changes were to due to the fact that the Prozac had disrupted the growth of the fish’s axons.
In the early ‘70s it was discovered that serotonin plays a role in depression and the hypothesis that increasing 5-HT neurotransmission would be a way to help combat depression became accepted. This lead to the development of selective serotonin-reuptake inhibitor fluoxetine, which is also known as Prozac, and was approved to treat depression in 1987.
Background
Prozac is a selective serotonin reuptake inhibitor antidepressant (SSRI). Serotonin is a neurotransmitter, which means it relays signals between cells in a brain. Commonly known as fluoxetine, Prozac is one of the most popular antidepressants and is ingested by the mouth, usually once a day in the morning.
Uses
Prozac is used to treat depression, bulimia, OCD, panic disorder and premenstrual dysphoric disorder. It can be used with other medications such as olanzapine (Zyprexa) to treat depression caused by bipolar disorder. About 50% of people treating their depression with an antidepressant find that their symptoms have been greatly minimized. However, Prozac can’t be used if certain other drugs are in use because a dangerous drug interaction may occur. For example, if a patient has taken an MAO inhibitor (including isocarboxazid, linezolid, phenelzine, rasagiline, selegiline and tranycypomine) in the last fourteen days, he/she is not allowed to use Prozac or must wait five weeks after stopping Prozac before taking an MAO inhibitor.
Prozac is sometimes prescribed to people who are sick and subsequently depressed. For example, cancer patients who develop major depression are often given Prozac.
How it Works
Prozac works by blocking the absorption of serotonin in the brain. The regulation of serotonin in the brain results in a more enhanced and stable mood because the regulation makes it easier for brain cells to communicate messages to each other. Also, SSRIs increase the amount of serotonin in the brain, which is another reason Prozac is thought to better the symptoms of depression.
Recent research suggests that antidepressants like Prozac don’t treat depression by altering the chemical imbalances in the brain, but rather that depression kills neurons in the brain while Prozac stimulates the growth of neurons.
SSRIs such as Prozac work by inhibiting SERT, a transporter, which pumps serotonin into the neurons. This shortens the time that serotonin has to deliver its signal, which increases serotonin function. Prozac also increases the amount of serotonin in the synaptic gap (the space between the neurons). The increased concentration of serotonin doesn’t give an explanation of how exactly SSRIs inhibit SERT and researchers are particularly puzzled by why it take weeks before SSRIs are fully active.
Side Effects
Although Prozac is used to treat depression, some people have suicidal thoughts when they first begin using it. This is mostly common in young people and there have been many instances of teenagers committing suicide where Prozac has thought to have triggered it.
If a pregnant woman takes Prozac, it may cause serious complications in the baby. Studies have shown that children exposed to antidepressants in the womb have worse motor development, lung problems, and a higher risk of birth defects.
To avoid side effects, a doctor may start the patient on a low dosage and gradually increase it. Similarly, side effects can become worse when one suddenly stops taking Prozac so the dosage will need to gradually decrease to avoid that.
Research
A University of Helsinki’s Neuroscience Center research project shows the affect of Prozac on a mouse’s brain. They put adult mice in a cage and repeatedly played a tone right before giving them an electric shock. They then moved the mice to a different cage where the same tone played but no electric shock followed. Previous research has shown that mice less than three weeks old quickly learn that the tone no longer means that a shock is coming but adults are unable to learn that and always fear what will happen after the tone. But, when the adult mice are given Prozac they’re able to learn that the tone no longer means a shock is coming. They found that Prozac minimizes fear in mice by increasing brain plasticity.
Alternatively, separate research found that fish swimming in water with Prozac in it had negative behavioral changes. They found that Prozac can alter the genes that control their behavior and made them anxious, anti-social, and homicidal. Male fish that were exposed to Prozac ignored female fish and females produced fewer eggs. They discovered that these changes were to due to the fact that the Prozac had disrupted the growth of the fish’s axons.
Glossary
|
MAO inhibitor- monoamine oxidase inhibitors are a class of medications used to treat depression
Neurons- A specialized cell transmitting nerve impulses; a nerve cell Neurotransmitters- A chemical substance that is released at the end of a nerve fiber by the arrival of a nerve impulse and by diffusing across the synapse or junction, causes the transfer of the impulse to another nerve fiber, a muscle fiber, or some other structure |
Serotonin-- A compound present in blood platelets and serum that constricts the blood vessels and acts as a neurotransmitter
SSRI-- Antidepressant Axon-- Long nerve fibers that transmit information to the body |
Works Cited
Bienkowski, B. (n.d.). Fish on Prozac Prove Anxious, Antisocial, Aggressive. Retrieved April 8, 2015, from http://www.scientificamerican.com/article/fish-on-prozac-prove-anxious-anti-social-agressive/
Prozac Uses, Dosage, Side Effects & Warnings. (n.d.). Retrieved April 4, 2015, from http://www.drugs.com/prozac.html
Prozac (fluoxetine). (n.d.). Retrieved April 5, 2015, from http://www.netdoctor.co.uk/depression/medicines/prozac.html
Jabr, F. (n.d.). Fearless Youth: Prozac Extinguishes Anxiety by Rejuvenating the Brain. Retrieved April 5, 2015, from http://www.scientificamerican.com/article/prozac-extinguishes-anxiety-rejuvenating-brain/
Prozac oral : Uses, Side Effects, Interactions, Pictures, Warnings & Dosing - WebMD. (n.d.). Retrieved April 8, 2015, from http://www.webmd.com/drugs/2/drug-6997/prozac-oral/details
What does fluoxetine do and how effective is it? (n.d.). Retrieved April 5, 2015, from http://www.nps.org.au/medicines/brain-and-nervous-system/antidepressant-medicines/fluoxetine/for-individuals/what-does-fluoxetine-do
Result Filters. (n.d.). Retrieved April 5, 2015, from http://www.ncbi.nlm.nih.gov/pubmed/1445777
Prozac Uses, Dosage, Side Effects & Warnings. (n.d.). Retrieved April 4, 2015, from http://www.drugs.com/prozac.html
Prozac (fluoxetine). (n.d.). Retrieved April 5, 2015, from http://www.netdoctor.co.uk/depression/medicines/prozac.html
Jabr, F. (n.d.). Fearless Youth: Prozac Extinguishes Anxiety by Rejuvenating the Brain. Retrieved April 5, 2015, from http://www.scientificamerican.com/article/prozac-extinguishes-anxiety-rejuvenating-brain/
Prozac oral : Uses, Side Effects, Interactions, Pictures, Warnings & Dosing - WebMD. (n.d.). Retrieved April 8, 2015, from http://www.webmd.com/drugs/2/drug-6997/prozac-oral/details
What does fluoxetine do and how effective is it? (n.d.). Retrieved April 5, 2015, from http://www.nps.org.au/medicines/brain-and-nervous-system/antidepressant-medicines/fluoxetine/for-individuals/what-does-fluoxetine-do
Result Filters. (n.d.). Retrieved April 5, 2015, from http://www.ncbi.nlm.nih.gov/pubmed/1445777
