hello my name is dr. Yolanda Pinkett I'm a geriatric psychiatrist who consults for a large home care agency in the Bronx and today I'd like to talk to you about the use of selective serotonin reuptake inhibitors or as they're more commonly known as SSRIs and the treatment of depression so first let's talk a little bit about serotonin which is a hormone that's found in various parts of the body not just the brain as you can see here serotonin can be found in the digestive tract the central nervous system the pineal gland which is responsible for our sick Kanyon rhythms and blood platelet cells which are responsible for clotting in the brain serotonin acts as a neurotransmitter and it transmits electrical impulses from one neuron to the next this is the action of serotonin this that has the greatest effect on mood so there many ways that serotonin regulates the body and brain functioning it can affect your mood sleep appetite sexual desire and cognition and changes in the level of serotonin can interfere with these functions and can lead to symptoms that we see in depression a decrease in serotonin as I said earlier can call us depressive symptoms and the levels of serotonin can be reduced in a number of ways there can be a low production of serotonin and brain cells a decrease in the number of receptor sites that bind serotonin on brain cells there can be an inability to bind properly to these receptor sites and there can also be a reduction in the storage of a precursor chemical which is called tryptophan tryptophan is used to make serotonin in brain cells the same way as it's used to make melatonin which regulates our sleep/wake cycles as you already know one of the most widely used treatments for serotonin deficiency are the SSRI and so let's talk a little bit about how SSRIs work so they bind to postsynaptic neurons and block the resorption of serotonin in the neurons synaptic region this causes an increase of serotonin levels for that neuron this allows for there to be more available serotonin binding in the postsynaptic cell receptor sites to make this point a little bit clearer let's look at the illustrate on the next slide so here you can appreciate that in the highlighted region serotonin is produced in the cell and carried by vesicles to the nerve ending of the presynaptic cell and then it's released into the synaptic region where it binds to receptor site and the postsynaptic nerve ending and this allows for the electrical impulses to be carried from the presynaptic nerve to the postsynaptic nerve and this is what regulates our bodily functions so if there's a decrease of serotonin in the synaptic space there's not going to be enough to bind to the receptor site in order to effectively carry these to effectively transmit these impulses from one nerve to the next and after the serotonin is done binding to a receptor sites it's usually reabsorbed into back into the presynaptic nerve ending well if the SSRIs are on board as you see here in the highlighted region they can block the resorption of serotonin back into the presynaptic nerve ending and this causes serotonin to stay in the synaptic region longer which allows for more time to bind to the receptor sites and more time for the neural impulses to be transmitted and for normal following functions to occur so staying in the synaptic region longer allows serotonin to regulate the functions of the body more effectively which can reduce the depressive symptoms so their different types of SSRIs there on the market today they've been around since 1987 with the introduction of prozac or fluoxetine as it's known by its generic name there are also others paxil zoloft celexa and lexapro that are all now available in their generic forms I just like to note that in older adults we need to be a little more careful about prescribing antidepressants we usually start with the very low doses for older adults and we go very slow and increasing the dose until we get to a therapeutic dose we use Prozac and paxil with caution and older adults for a few reasons first these two are metabolized in the liver in such a way that they can cause drug drug interactions with many of the other drugs that older people take secondly paxil can cause some slowing of a person's cognitive functioning which happens more in older adults and can also cause sedation which can cause a fall risk for older adults so we try to use this very sparingly and older adults also celexa has some cardiac side effects that can be related to very severe side effects such as palpitations fainting and said in debt and there's been a limit on the dose range for selects and older adults that we try to use any more than 20 milligrams because these effects are seen at ranges above 20 I'd also like to call your attention to another SSRI luvox which I'll mention here because it is an SSRI to be complete but it's not used for the treatment of depression choose for the treatment LCD so we rarely see this used for depression so there are many side effects that you see with SSRIs these are some of the most common I like to bring your attention to a few that also may be symptoms of depression such as headache reduced libido insomnia patients may complain about these side effects after the initiation of an SSRI but it's important to ask the patient when the symptom actually started it can be a symptom of the depression that they're just not being aware of that they may blame on medication but it's actually more symptom of depression so it's very important to ask when did the symptoms start if a patient is having difficulty tolerating an SSRI because of the side effects involved and they don't go away after about a week it's very important to alert the prescribing physician so that the medication can either be reduced adjust it in some way or switch to a different medication and the first line of activity would be to maybe switch to a different SSRI because they don't all have the same side effects and would all affect the patient in the same way so just to end I just wanted to alert you to some of the contraindications or interactions that can occur with SSRIs these antidepressants can increase the blood concentration of medications like warfarin digoxin these medications can be monitored in some aspects by lab result by lab tests but some can't so it's important to know that this interaction can occur and to just be mindful of it and to maybe reduce an SSRI dose if you see that it's interfering with another medication also patients with chronic pain arthritis may use ibuprofen naproxen and on a more frequent basis which can reduce the levels of SSRIs so the SSRI might need to be increased in these cases and lastly certain agents like alcohol diuretics ambien and other agents can increase SSRI levels which in these cases we need to be aware because an increase of serotonin in the body can cause some mental status changes hyperthermia hypertension different side effects that we need to be aware of because if that's the case these medications need to be reduced and levels of serotonin have very high levels of serotonin in the body can produce something called a serotonin syndrome which may lead to death in some patients so it's very important to monitor patients that have been put on these medications that are also using agents like diuretics and alcohol on a regular basis this ends our discussion on SSRIs thank you for participating I hope you enjoyed my presentation and I hope you will also visit our web library for our other mini lecture series topics thank you