Final answer:
The interaction between Pethidine and Tranylcypromine is mediated by serotonin. This combination can lead to serotonin syndrome due to the inhibition of serotonin breakdown by MAOIs and potential increase of serotonin release by opioids. It illustrates the necessity of careful medical supervision to prevent adverse effects.
Step-by-step explanation:
The drug interaction mediated by serotonin is between Pethidine and Tranylcypromine. Pethidine is an opioid analgesic, and Tranylcypromine is a type of monoamine oxidase inhibitor (MAOI).
When these two drugs are taken together, there is a risk for a serotonin syndrome, which is a potentially dangerous increase in serotonin levels.
This occurs because MAOIs inhibit the breakdown of serotonin, and opioids like Pethidine can increase its release, leading to an accumulation of serotonin.
Tranylcypromine, as an MAOI, prevents the breakdown of neurotransmitters including serotonin, thereby raising the potential for increased serotonin levels.
On the other hand, the reuptake or recycling of serotonin back into the presynaptic neuron is blocked by Selective serotonin reuptake inhibitors (SSRIs), leading to increased serotonin in the synaptic cleft.
The combination of drugs affecting serotonin levels can lead to an excessive amount, resulting in adverse events like the serotonin syndrome. Therefore, it's crucial to manage these drug interactions carefully under medical supervision.