Brief Answer:
Amphetamine must be considered as a possible cause as well.

Detailed Answer:
I read your question carefully and I understand your concern.

Aggressiveness and being moody is not a typical side effect of duloxetin, actually usually it helps alleviate those. It is not impossible, some cases have been reported, as it is a drug acting on neurotransmitter levels and in certain individuals may sway the balance in a different direction. It is very rare though.

So given the fact that he is under other medications I would invite you to consider the possibility of those playing a role as well. Those issues are much more commonly a side effect of amphetamine, so that should be regarded as the primary suspect and its use and dosage be reconsidered (you do not provide much information on why he takes amphetamine and since when).

If amphetamine is really necessary at the current dosage and you are certain symptoms started only after adding duloxetine, then it should be interrupted. It is not a vital drug for shoulder pain, doesn't affect the course of the condition only reduces pain. Other options such as gabapentin may be considered for that purpose.

I remain at your disposal for other questions.

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Brief Answer:
Read below

Detailed Answer:
Thank you for the additional information, I suspected that was the reason for amphetamine use. Still not sure why he's taking baclofen for, though it is not likely to cause those side effects.

So the options are 2. One possibility is to attempt to reduce amphetamine dosage. The other as I said would be to remove Duloxetine. Of course there is no clear cut answer. If he has been taking amphetamine for a long time without any side effects and the issues you describe started with duloxetine therapy then I would choose to interrupt duloxetine.
If on the other hand they have both been initiated recently then amphetamine would be the most suspect drug for those side effects and should either be reduced or even interrupted if that is not enough.
Of course any change should also be discussed with prescribing doctor.

Let me know if I can further assist you.

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Brief Answer:
Read below.

Detailed Answer:
Hello again. Yes finasteride is for the hair loss and baclofen is a muscle relaxant, but what I meant why was a muscle relaxant needed, it may be used in many different conditions. Since you do not mention other conditions I assume in this case it must have been prescribed for the back and shoulder muscles.
Anyway it doesn't change my previous opinion, the recommendation remains the same.

I hope to have been of help.

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Brief Answer:
I would reduce duloxetine

Detailed Answer:
Thank you for the info.

Amphetamine dose is not high at 10 mg.

Duloxetine on the other hand at a total of 120 mg per day is at the highest possible dose. Usually for musculoskeletal pain a daily dose of 60 mg is used. So if symptoms have started with duloxetine initiation I would reduce it at by half, either 30 mg capsules twice a day, or a 60 mg capsule in the evening.

Hope that leads to improvement of his mood changes.

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Brief Answer:
If he has been taking this dosage for some time yes, gradually.

Detailed Answer:
Yes it would be advisable to reduce it gradually. That is if he has been on this dosage for some time, at least a month (if only recently then I think he can safely go straight to 60 mg/day).
I would go to 90 mg/d for a month (30 mg morning and 60 mg in the evening) and then to the suggested dosage of 60 mg a day.

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