Fluvoxamine has the highest sigma-1 affinity by far. Fluoxetine's affinity is about an order of magnitude lower.
We don't even know if sigma-1 is responsible for the effects observed, but it wouldn't make sense to give someone Fluoxetine instead of Fluvoxamine (which is also widely available), especially when it would require overdose levels of Fluoxetine to achieve similar sigma-1 effects.
We don't even know if sigma-1 is responsible for the effects observed, but it wouldn't make sense to give someone Fluoxetine instead of Fluvoxamine (which is also widely available), especially when it would require overdose levels of Fluoxetine to achieve similar sigma-1 effects.
More numbers available in the full text here: https://pubmed.ncbi.nlm.nih.gov/24508523/