Antidepressants Flashcards
What are classifications of antidepressants
Monamine oxidase inhibitors
Tricyclic Antidepressants
Selective serotonin reuptake inhibitors
Selective noradrenaline reuptake inhibitors
Selective serotonin and noradrenaline reuptake inhibitors ( SSNRIS)
New developments Ketamine , psilocybin
Why are Monamine oxidase inhibitors used ?
Used as a last line of treatment after tricyclics and SSRIs .
What is monoamine oxidase inhibitors most useful for ?
Those who have phobic or hypochondriac element to their depression
Mode of action
Monamine oxidase is an enzyme in the body that breaks down noradrenaline. They inhibit the action of Monamine oxidase therefore increasing the levels of noradrenaline . They can cause the effect called the ‘cheese effect ‘ which is associated with a substance called tyramine .
What is tyramine
A substance normally broken down in the gut by Monamine oxidase ,when Monamine oxidase are taken they prevent tyramine from being broken down .
It’s present in certain foods , when a person takes these foods and is on MAOIs there is a serious rise in their blood pressure.
What foods include tyramine
Cheese ,bovril salami , beer,soy sauce
What other food should also be avoided
Over ripe or food that is going off for example meat,fish ,poultry
Symptoms
Throbbing headaches ,high temp,stiff neck ,these could be an indication to a dangerous rise in blood pressure.
Dizziness ,postural hypotension,sexual dysfunction
Indications for use
Sedative action,useful in agitated depression with sleep disturbance
Mode of action
Tricyclics inhibit the reuptake of noradrenaline and serotonin increasing both these neurotransmitters that have a non selective action .
Side effects
Cardio toxic ,dangerous on overdose and potentially fatal
Antimuscarinic side effects
Dry mouth ,constipation ,blurred vision and urinary retention
Other side effects
Tachycardia ,hypotension ,arrhythmias ,sexual dysfunction ,nausea and vomitting ,weight gain and taste disturbance .
Tricyclic antidepressants
Amitriptyline hydrochloride (triptafen , tryptizol)
Clomipramine hydrochloride (Anafril)
Dosulepin hydrochloride
Selective serotonin reuptake inhibitors
Depression
Anxiety
Treatment of OCD,panic disorder ,bulimia nervosa
Mode of action
Selectively inhibit the reuptake of serotonin thereby increasing levels in the brain
Are selective serotonin reuptake inhibitors cardio toxic
No therefore safer on overdose
Gastrointestinal side effects are common
E.g nausea
Side effects
Sexual dysfunction is widely reported and may continue after medication is stopped
Hypersensitivity reactions including rash
Increased risk of bleeding
Fluoxetine (Prozac)
Sertealine (citalopram, escitalopram)
What are SSRIs useful for
Depression with fatigue and apathy can increase energy and drive
Mode of action
Inhibit the reuptake of noradrenaline therefore increasing levels in the brain
Other side effects
Insomnia,sweatiness ,tiredness,postural hypotension
Generalised anxiety disorder
Mode of action - inhibits the reuptake of both serotonin and noradrenaline
Side effects
Nausea,headache,insomnia example venalfaxine
New developments
Ketamine - dissociative anaesthetic person feels discontinued or detached
Clinical trials show some promising results
Psilocybin
A psychadelic - in small doses has shown some promising results in trials for depression
