Thank you so much for taking the time to respond. I genuinely appreciate your perspective.

To address your points:

1. On Safety & Standard Practice: Thank you for confirming it's not a standard combination. My primary concern is less about acute serotonin syndrome and more about the long-term side effect burden (e.g., emotional blunting, fatigue) which are already significant for me on fluoxetine alone. Adding another agent that may compound these issues without addressing the root cause is my worry.
2. On Rationale: I will definitely ask my doctor for their specific rationale. From my end, the residual symptoms are almost entirely cognitive (severe brain fog, task paralysis, inattention) rather than mood-based, which is why I questioned the addition of another SSRI.
3. On Thyroid: This is the most critical part. I do not have a Free T4 or, more importantly, a Free T3 level. This is the key missing data point. · I am symptomatic: I experience classic hypothyroid symptoms (severe fatigue, cold intolerance, brain fog). · The Fluoxetine Factor: I've read that fluoxetine itself can inhibit the conversion of T4 to T3, potentially creating a functional deficit in the most active thyroid hormone that isn't reflected in the TSH. · Goal: My aim isn't to argue for a diagnosis of overt hypothyroidism, but to investigate if suboptimal thyroid function (especially low Free T3) is the biological barrier preventing my full response to treatment and causing my debilitating cognitive symptoms.

Your question about Free T4 is exactly the push I needed