Another antidepressant that has activity against enteroviruses and CVB3 is
Pirlindole
I have just been looking at the
pirlindole study again, and as you indicate, pirlindole is potently antiviral for CVB3
and other enteroviruses. Specifically, the study says it is antiviral for
enterovirus-B species, which includes coxsackievirus B and echovirus — the enteroviruses linked to ME/CFS.
So pirlindole will likely have antiviral activity against a range of coxsackievirus B and echovirus serotypes.
The study found that the EC50 concentration of pirlindole (in a cell line in vitro) was 7.7 μM. EC50 = the concentration which inhibits viral replication by 50%. And they found that there were no cytotoxic effects on the cells at concentrations as high as 100 μM.
In order to achieve a 7.7 μM concentration in your body tissues, I calculated (using
this equation) that an oral pirlindole dose of
280 mg would be required. This dose would then reduce viral replication by 50%. In terms of antidepressant dosing of pirlindole, it says
here that:
The initial dose is 50-100mg 2 times per day, the dose is gradually increased by 50mg to 150-300mg/day.
The maximum recommended dose is 400mg/day, divided into 2 parts. After the therapeutic effect has been achieved the treatment should be maintained during 2-4 weeks, after that the dose is gradually reduced.
So with pirlindole, you should get some antiviral effects with the maximum recommended antidepressant dose of 400 mg daily. Although it not an ideal l situation, as really you would want to go up to the 100 μM concentration which the study showed was still safe for cells in vitro, and will have much more potent antiviral effects. But 100 μM would correspond to an oral pirlindole dose of around 3.6 grams, which I guess is far too high, and this dose level may well have dangerous side effects.
So the situation with pirlindole seems similar to that of fluoxetine: you do get some antiviral effects at normal antidepressant doses, but the really strong antiviral effects are unfortunately only obtained at dose levels beyond the maximum antidepressant dose.
Pirlindole would probably be a little better tolerated than fluoxetine, though; and pirlindole has also been
shown to be helpful for fibromyalgia.
The problem for me is that Pirlindole is only available in Russia it seems, so I can't personally order it due to how customs work in my country
Pirlindole costs £10 for 50 x 50 mg pills at the prescription-free
rupharma.com (a reliable Russian pharmacy I used several times).
rupharma.com also has a sister company called
mospharma.com who specialize in getting drugs to patients in countries whose customs are very strict, such as certain EU countries, as well as Australia and Canada.