Can Strattera cause paranoia?

It did in my case.
I was only on a modest dose, combined with a modest dose of Prozac. This has been a scary mix for me....
I began to sleep very little and eat very little. I wondered how I was getting away with so little of either. I really wasn't. The first sign was that I began to have the shakes. At first it was only occasionally. Eventually it was a perpetual problem.
Then I began to be very emotional. Crying jags that might last a couple hours, especially in the wee hours of the night when I couldn't sleep..
The paranoia took a while, sneaking up on me. I began to have irrational fears.
Although I was already on some sleep meds, I had to get an adjustment to get some decent sleep. That seemed to make the paranoia, crying and shakes go away. Mostly.
Be very careful with these meds if they take your appetite and your sleep. In particular, don't assume it's o.k. if you aren't sleeping. Even though I wasn't sleeping much, I still rarely felt sleepy or fatigued. That's the tricky part. My sleep deprivation manifested in other, seemingly unrelated ways....