Tricyclic Antidepressants (TCAs)
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Mental Health Drugs
- Bupropion
- SNRIs
- SSRIs
- MAOIs
- Tricyclic Antidepressants (TCAs)
- Extrapyramidal Symptoms (EPS)
- Lithium
- Trazodone
- Buspirone
- Mirtazapine
- Benzodiazepines
- Barbiturates
- Zolpidem
- Typical Antipsychotics
- Atypical Antipsychotics
- Lithium (Old)
- Bupropion (Old)
- SNRIs (Old)
- MAOIs (Old)
- Amphetamines (Old)
Summary
The tricyclic antidepressants include imipramine, desipramine, doxepin, clomipramine, nortriptyline, and amitriptyline.
Tricyclic antidepressants work by inhibiting the reuptake of serotonin and norepinephrine. Their effects are often delayed by 2 weeks.
TCAs are used to treat depression, bed-wetting, insomnia, neuropathic pain and OCD.
Side effects of tricyclic antidepressants include sedation and arrhythmias. They may also increase the risk of suicide. Overdosing on these drugs can be lethal. Other side effects include orthostatic hypotension and anticholinergic effects.
TCAs are usually recommended to be taken at night. They should not be stopped abruptly.
Avoid combining tricyclic antidepressants with MAO inhibitors.
Key Points
- Tricyclic Antidepressants
- Drug Names
- Amitriptyline (Elavil, Vanatrip)
- Nortriptyline (Pamelor, Aventyl)
- Imipramine (Tofranil)
- Desipramine (Norpramin)
- Clomipramine (Anafranil)
- Doxepin (Silenor)
- Mechanism
- Blocks reuptake of serotonin and norepinephrine
- This increases the amount of these neurotransmitters in the synaptic cleft and intensifies their effect
- Delayed Effect (~2 Weeks)
- It can take several weeks before the intended effect is seen
- Patients should be informed about this delay to manage expectations. Emphasize the importance of continuing medication even if immediate effects aren't noticed
- Blocks reuptake of serotonin and norepinephrine
- Clinical Use
- Depression
- Including depression associated with bipolar disorder
- Used less frequently for this purpose due to availability of newer antidepressants with fewer side effects
- Neuropathic Pain
- Including pain from fibromyalgia and diabetic neuropathy
- Often effective at lower doses than those used for depression
- Obsessive Compulsive Disorder (OCD)
- Insomnia
- Sedating properties can be beneficial for patients with depression and sleep disturbances
- Bed Wetting
- Imipramine is often used for this purpose in children
- Depression
- Side Effects
- Orthostatic Hypotension (Dizziness)
- Instruct patient to change positions slowly to prevent dizziness and falls
- Particularly important in elderly patients or those with cardiovascular issues
- Anticholinergic Effects
- Constipation
- Encourage diet high in fiber and fluids
- Blurry Vision
- Can affect ability to drive or perform tasks requiring clear vision
- Dry Mouth
- Can be relieved by chewing sugarless gum, sucking on hard candies, or taking frequent sips of water
- Urinary Retention
- Constipation
- Sedation
- The patient should not drive until they know how the medication affects them
- Sedation may diminish over time
- Arrhythmias
- Regular ECG monitoring may be necessary, especially in patients with heart conditions
- Increases suicide risk
- Most common within the first few weeks of treatment
- The patient may begin to have more energy, without improvement in mood. This puts them at a higher risk of suicide.
- Lethal in overdose
- One of the reasons tricyclic antidepressants aren’t used as often anymore is because of how dangerous they are in overdose
- Seizures
- Tricyclic antidepressants lower the seizure threshold, making patients taking them more susceptible to seizures
- Not usually recommended in patients with history of seizures
- Orthostatic Hypotension (Dizziness)
- Administration
- Take at bedtime
- Tricyclic has a sedative effect, so they’re best taken at night to avoid daytime drowsiness
- Do not stop abruptly
- To discontinue the medication, the dose must be tapered down slowly
- Take at bedtime
- Interactions
- Avoid MAOIs
- Combining TCAs with MAOIs can lead to serotonin syndrome, a potentially life-threatening condition
- Avoid alcohol
- Avoid MAOIs
- Drug Names