Flashcards in TCAs Deck (16):
Name a common TCAs?
How do TCAs work?
Inhibit neuronal reuptake of serotonin (5-HT) and noradrenaline from the synaptic cleft, thereby increasing their availability for neurotransmission.
TCAs also block other receptors such as muscarinic, histamine (H1), α-adrenergic (α1 and α2) and dopamine (D2) receptors
What pain relief medication works on a similar basis to TCAS?
Tramadol also blocks NA and serotonin receptor whilst also working on the opioid mu receptor
What are the common uses for TCAs?
1. Moderate to severe depression - when SSRIs do not work
2. Neuropathic pain - although not licenced
What are the contraindications of using TCAs?
Do not use with monoamine oxidase inhibitors as they both work to increase the levels of serotonin and NA so can cause hypertension, hyperthermia and serotonin syndrome
When should TCAs be used with caution?
= More at risk of adverse effects
Raised intraocular pressure/ Acute angle glaucoma
= can be worsened by antimuscarininc effects
What are the common interactions with TCAs?
Monoamine oxidase inhibitors
TCAs can enhance antimuscarinic, sedative or hypotensive adverse effects of other drugs.
What are the antimuscarinic side effects of TCAs?
What are the CV side effects of TCAs?
ECG changes (prolonges QT and QRS complexes)
What are the histamine and alpha blocker side effects of TCAs?
What are the CNS side effects of TCAs?
Why can TCAs worsen psychosis and bipolar?
they can cause convulsions hallucinations and mania
What are the overdose side effects of TCAs?
What are the with-drawl side effects of TCAs?
Influenza like symptoms
How are TCAs excreted?
Metabolised by liver
Excreted by kidneys