Most poisoning presentations are from an acute ingestion; however chronic poisoning can also present acutely. Tricyclic Antidepressants have their toxic effects through
action at 4 main receptors involving antagonism/inhibition
at: Central and peripheral acetylcholine receptors. α adrenergic receptors peripherally.
How do TCAs cause overdose?
Tricyclic antidepressants have a narrow therapeutic index and, therefore, become potent cardiovascular and central nervous system toxins in moderate doses. Complications include effects of prolonged hypotension, cardiac arrhythmias, and seizure.
Death results from cardiovascular collapse
.
Why are tricyclic antidepressants so toxic in overdose?
TCAs are rapidly absorbed in the gastrointestinal tract. However, following an overdose, owing to the inherent anticholinergic effects,
TCAs may decrease the gastrointestinal motility and cause delayed absorption and toxicity
. Coingestion of other anticholinergic medications may cause more erratic absorption.
What is the main problem with tricyclic antidepressants?
Some tricyclic antidepressants are more likely to cause side effects that affect safety, such as: Disorientation or confusion, particularly in older people when the dosage is too high. Increased or irregular heart rate. More-
frequent seizures in
people who have seizures.
Why do tricyclic antidepressants cause anticholinergic effects?
Tricyclic antidepressants (TCAs) have a number of common side effects that require careful management. Anticholinergic effects (including dry mouth, blurry vision, urinary hesitancy, constipation, tachycardia, and delirium) that result from
the blockade of muscarinic cholinergic receptors
can occur with use of TCAs.
What is the most cardiotoxic antidepressant?
Among SSRIs,
Citalopram
is known to have the highest cardiotoxic capacity in a dose-dependent fashion.
What are the symptoms of serotonin syndrome?
- Agitation or restlessness.
- Confusion.
- Rapid heart rate and high blood pressure.
- Dilated pupils.
- Loss of muscle coordination or twitching muscles.
- Muscle rigidity.
- Heavy sweating.
- Diarrhea.
What are the side effects of too much amitriptyline?
Taking too much amitriptyline can cause serious side effects such as a
change in your heartbeat, seizures or fits
.
What is the antidote for beta blocker overdose?
For cases of beta-blocker poisoning where symptomatic bradycardia and hypotension are present,
high-dose glucagon
is considered the first-line antidote. For cases of CCB poisoning where cardiotoxicity is evident, a combination of calcium and epinephrine should be used initially, reserving HDIDK for refractory cases.
Can amitriptyline cause sudden death?
Conclusions: Our data suggest that SSRI antidepressants and TCAs in doses of less than 100 mg (amitriptyline equivalents)
did not increase the risk of sudden cardiac death
.
What are the top 5 antidepressants?
- Celexa (citalopram)
- Wellbutrin (bupropion)
- Paxil (paroxetine)
- Savella (milnacipran)
- Prozac (fluoxetine)
- Cymbalta (duloxetine)
- Luvox (fluvoxamine)
- Vestra (reboxetine)
Why are SSRIs better than tricyclics?
SSRIs are more selective for serotonin transporters. While they are usually associated with fewer side effects, SSRIs can still cause adverse effects. Usually, SSRIs are
much easier to tolerate than tricyclic antidepressants since the side effect profile is better for
most people.
What is the oldest antidepressant?
The 1950s saw the clinical introduction of the first two specifically antidepressant drugs: iproniazid, a monoamine-oxidase inhibitor that had been used in the treatment of tuberculosis, and
imipramine
, the first drug in the tricyclic antidepressant family.
Why are tricyclics bad?
Tricyclic antidepressants can cause harmful side effects if you take them with certain medications, including epinephrine (Epi-Pen) and cimetidine (Tagamet). Tricyclic antidepressants
can increase the effects of epinephrine on your heart
. This can lead to high blood pressure and problems with your heart rhythm.
What is a antidepressant with no anticholinergic effects?
SSRIs are the initial antidepressants of choice for uncomplicated depression because of their minimal anticholinergic effects. They have the advantage of ease of dosing and low toxicity in overdose.
Which tricyclic antidepressant is best for anxiety?
Physicians use tricyclic antidepressants in the treatment of panic disorder, PTSD, generalized anxiety and depression that occurs with anxiety. Of this family,
imipramine
has been the focus of most of the panic treatment research.
