Pharmacology Mini # 6: Antidepressant Medications

This video discusses SSRI, SNRI, Atypical Antipsychotics, TCA, and MAOI’s

Welcome to pharmacology mini number six where we’re going to cover antidepressant medications antidepressant medications primarily work to increase the availability of serotonin norepinephrine and dopamine neurotransmitters in the synaptic cleft it’s used to treat depression bipolar disorder obsessive compulsive disorder bulimia nervosa premenstrual dysphoria panic

Disorder ptsd social anxiety and generalized anxiety there’s five classes of antidepressant medications the selective serotonin reuptake inhibitors or ssris serotonin norepinephrine reuptake inhibitors or snris atypic atypical antidepressants tricyclic antidepressants or tcas and monoamine oxidase inhibitors also called maois we’re going to talk about the selective

Serotonin reuptake inhibitors and the serotonin norepinephrine reuptake inhibitors together because they’re very similar chemically and have a lot of the same um characteristics as each other so the purpose of a selective serotonin reuptake inhibitor is to inhibit serotonin reuptake which increases the amount of serotonin available at the synaptic cleft with snris it

Inhibits serotonin reuptake as well as norepinephrine reuptake both have a half-life that’s fairly long compared to other medications so it takes about one to two weeks before we start to see any therapeutic effects from these medications and it takes four to six weeks before we see a full therapeutic effect typically with any antidepressant we see the physical

Symptoms start to improve more quickly than some of the mental or emotional symptoms so if you have a patient that has suicidal ideation alongside their depression they may not have the energy or the focus to come up with a plan however when they start an antidepressant after about two weeks when they start getting more physical energy and focus they suddenly

Have that ability to create a plan and carry it out before the mental and emotional effects start to take place so we do want to especially monitor our patients with suicidal ideation that are starting an antidepressant for those first two weeks of start for any suicidal thoughts or suicidal behaviors because they are going to be at that higher risk between two

To four two to six weeks examples of ssris include paroxetine or also called paxil sertaline called zoloft acetylapram called lexapro citalopram which is celexa fluoxetine which is called prozac and fluvoxamine which is called leuvox as you can see a lot of these medications end in either pram or amine examples of snris are venaflaxine also called effexor does

Venaflexine also called pristique daloxetine also called cymbalta and level melanocyte sorry levomin milnesopram also called fatisma the complications of both ssris and snris include both acute and long-term side effects and possible adverse reactions most acute complications tend to resolve after a couple of weeks long-term complications will last a little

Bit longer so at initially starting these medications the patient may have increased nausea and vomiting diaphoresis tremors fatigue drowsiness initial weight loss even though that can turn into a long-term weight gain and suicidal ideation our long-term symptoms are going to include insomnia which if our patients are having insomnia from a medication we would

Want to make sure that they’re taking that medication earlier in the day so that by the time it’s run through the body it won’t impact their sleep as much other long-term effects could include a headache sexual dysfunction weight gain gi bleed hyponatremia serotonin syndrome which is a medical emergency that we’ll talk about later ruxism withdrawal postural

Hypotension continued suicidal ideation rash and blurred vision for interactions for ssri and snri medications we want to know that most of these medications are pregnancy risk category c or d so most of them are not typically recommended in pregnancy or breastfeeding these medications do interact quite a bit with herbal supplements for example st john’s wort is

An herbal supplement that’s used for treating symptoms of depression along with a lot of other um ailments and it increases serotonin so when we combine it with an ssri or an snri that patient’s going to be at higher risk for that medical emergency called serotonin syndrome kava is another herbal supplement that interacts with just snris and valerian which also

Interacts with snris all medications that we’re going to talk about today tend to interact with maois as well which are monoamine oxidase inhibitors and we’ll talk a little bit about both serotonin syndrome and hypertensive crisis which can develop if these medications are taken not only the same time as an maoi or but within 14 days of stopping an maoi they

Can interact with tricyclic antidepressants again because of that serotonin syndrome it can interact with antiplatelet and anticoagulant medications and we want to be cautious or avoid use in patients that have liver failure kidney failure seizure disorders history of gi bleed because remember that can be a long-term complication as well as patients that have

Bipolar disorder mania seizure disorder a recent myocardial infarction or interstitial lung disease moving on to our atypical antidepressants so these are used to treat depression smoking cessation seasonal affective disorder and adhd or attention deficit hyperactivity disorder the way that atypical antidepressants work is they tend to inhibit norepinephrine

And dopamine reuptake examples of these often end in z-o-d-o-n-e so our examples are bupropion which is wellbutrin the lazadone which is vibrid mertazapine which is romneron and the fazodone which is sir zone intrazodone which can also be called deserel or electro the side effects of atypical antidepressants include anticholinergic effects so remember this is

Things like having a headache a dry mouth gi distress constipation tachycardia hypertension restlessness and insomnia if our patients do develop these side effects we can encourage them to eat sugar chew sugarless gum suck on a sugarless candy to kind of help with that dry mouth for constipation we would want them to increase their fiber intake increase fluids

All of that they can develop nausea and vomiting so we would encourage them to take the medications with food it can contribute to anorexia or weight loss so if you have a patient that has um too low of a bmi or if they have symptoms of anorexia nervosa an atypical antidepressant would not be an appropriate medication for them it can also cause seizures transit on

Specifically can cause preappism intrazodone and mertazapine can cause sedation so those are typically given more towards the evening so it can help the patient with sleep contraindications and interactions is that they’re all pregnancy risk category b and they do interact with maois and velazadone specifically interacts with grapefruit juice then we have our

Tricyclic antidepressants so these block reuptake of norepinephrine and serotonin and they can have the same effect on dopamine sometimes as well these medications take about 10 to 14 days for start of therapeutic effect and four to eight weeks for full therapeutic effect the purpose of tricyclic antidepressants is to treat bipolar disorder depressive disorders

Neuropathic pain fibromyalgia anxiety ocd insomnia and adhd examples of this include medications that tend to end in pramine so amitriptyline is elevil imipramine is tophernyl nor tryptolene is pamelor doxapin amoxipine which is ascending trimipramine which is sermontil desopramine which is norepromine and clamoprine which is anaphoral the side effects of

Tricyclic antidepressants include orthostatic hypotension so we would want to educate our patients to make sure that they’re getting up slowly and sitting down if they feel any dizziness when changing positions we can also see those anti-cholinergic effects that we talked about with the atypical antidepressants they can develop sedation so a lot of times these

Medications will be given in the evening toxicity of tricyclic antidepressants can happen quite easily so we would want to get a baseline ecg and vital signs just in case it causes any heart arrhythmias it does decrease the seizure threshold so they’re at increased risk for having seizures it can cause excessive sweating and that suicidal ideation that i talked

About earlier contraindications for this medication includes that it is pregnancy category c we would not give it to any patients that have seizure disorders or a history of a myocardial infarction and we would want to use it with caution in the elderly those with cad diabetes liver or kidney failure respiratory disorder urinary retention and that’s because

Of the anticholinergic effects glaucoma bph or hyperthyroidism tricyclic antidepressants also interact with quite a few medications so we know that it interacts with malis and again that can cause both serotonin syndrome as well as hypertension it interacts with saint john’s wort again because it can cause serotonin syndrome anticholinergic medications because

Anticholinergic effects are part of the side effects sympathematics which can increase dopamine and ephedrine as well as amphetamines and epinephrine effects if used with alcohol it can increase dns depression same thing with benzodiazepines as well as opioids and we also wouldn’t want to give it with an antihistamine because that can also cause cns depression

Ways that we can treat those anti-cholinergic effects as i mentioned earlier we can have them chew sugarless gum or have sugarless candies they can sip water frequently we would want to educate our patients to wear sunglasses in the sun eat foods high in fiber exercise regularly drink two to three liters of fluid and void before taking any medications and while i

Have this listed under tricyclic antidepressants these interventions are appropriate for any medication that has anti-cholinergic effects as a side effect we would also want to educate our patients that are taking anti or tricyclic antidepressants to take them at bedtime and that many of these medications will only be given in a one week supply because there is

Such a high risk for suicidal ideation and toxicity once the patient is stabilized on these medications and they’re not showing any symptoms of suicidal ideation we can give them a supply that lasts a little bit longer than a week then lastly we have our monoamine oxidase inhibitors so these block monoamine oxidase enzymes which are enzymes that typically break

Down norepinephrine dopamine serotonin and tyramine so when we block the enzymes that are breaking it down we’re increasing the amount of norepinephrine dopamine serotonin and tyramine available at the synaptic gap it does take about two to four weeks for therapeutic effect and it takes about 14 days for the medication to leave the system when discontinued so

We’ll talk about a lot of the interactions that maois have and we would want to avoid using any of those medications or foods within two weeks of stopping the medication maois are effective in treating depression bulimia nervosa panic disorder social anxiety disorder generalized anxiety disorder ocd and ptsd while these are effective in treating all of those

Disorders this tends to be a later therapy or a last therapy that we would try just because the side effects in the interactions with other medications is so severe so examples of maois are nardyl marplan carnate aldopryl or zelpar and this aldepril or zelpar also called celgoline can be used as a transdermal patch so side effects is it can cause cns stimulation

It can also cause orthostatic hypotension hypertensive crisis and a rash especially for that transdermal patch it interacts with some sympathomatics which can cause hypertensive crisis tricyclic antidepressants also cause hypertensive crisis it can cause serotonin syndrome by taking ssris it would be contraindicated with anti-hypertensives the parroting it can

Cause hyperpryrexia we would want not want to take it with tyramine rich foods because that can also place the patient in hypertensive crisis it’s contraindicated with vasopressors because that can cause hypertension and it’s also contraindicated with general anesthesia we would want to use caution in pregnancy because it is a pregnancy category c and we’d also

Want to use caution with those that have diabetes seizure disorders theo chromatocytoma heart failure cvd and real renal failure we’d want to stop use for 14 days before starting another antidepressant and we would also want to educate our patients on any tyramine rich food so that they can avoid it while taking an maoi in addition to all of the antidepressant

Classes that we talked about there are some non-antidepressants that we can use to treat depression most of these are antipsychotic medications and they include abilify which is augmented with ssris seroquil which can also be used for anxiety sleep depression and bipolar disorder rig salty which is an adjunctive therapy for resistant types of depression so those

Are types of depression that haven’t responded to antidepressants if we add this result to you to it it can help with treatment there’s vrylar which is helpful for bipolar mania as well as mixed bipolar latuto which is helpful for bipolar depression and trintellix or brintalics so now on to those medical emergencies that i talked about there’s two main ones that

We think about when we talk about antidepressant medications and that’s serotonin syndrome which is common with almost all forms of antidepressants and hypertensive crisis which is particularly risk when we take maois so for serotonin syndrome this is when toxic levels of serotonin develop this is from combining different medications that increase serotonin with

Herbal supplements or it can happen with any dose changes to a medication that increases serotonin we typically start seeing symptoms within 2 to 72 hours of treatment the symptoms range from mild to severe with mild symptoms being agitation restlessness insomnia confusion tachycardia hypertension dilated pupils muscle twitching and rigidity sweating diarrhea

Headaches shivering and goosebumps and more severe symptoms being extreme fever tremors seizures arrhythmias coma and death our treatment when our patient develops serotonin syndrome is to stop the medication that’s increasing the serotonin level and treat them symptomatically so to stop the medications we could also give a serotonin receptor blockade to try and

Lower that serotonin level symptomatically we can provide them with cooling blankets so they don’t develop hyperthermia we can give them anti-convulsants to try and prevent any seizure activity and we can provide artificial ventilation and resuscitation if necessary then hypertensive crisis is a common reaction to maois when taken with tyramine or other medications

So i mentioned earlier that we would want to educate our patients on tyramine-rich foods so these are foods that are aged cheeses smoked meats avocados figs fermented fruits protein supplements red meats soy sauce and alcohol symptoms of hypertensive crisis include headaches nausea tachycardia blood pressure greater than 180 systolically in 120 diastolically

Stroke and possible death the treatment for this is regatine iv or procardia which can be given sublingual we would want to do telemetry monitoring and cardiorespiratory support that wraps up our mini lecture on antidepressant medications

Transcribed from video
Pharmacology Mini # 6: Antidepressant Medications By Erin Micale