Hi
@BOAG -
My first thought is to ask your doc about Clonidine. It lowers blood pressure, which helps with sleep. It's the same principal as Prazosin, which is another blood-pressure med that is often prescribed off-label for people with PTSD, to help with sleep/nightmares.
The advantage of Clonidine is that it's also used off-label as an opioid blocker. So, if your doctor had experience with clonidine, and thought that it would work as well for you as the naltrexone, you might take care of two issues with one med (which is always preferable, whenever possible).
Trazadone is often prescribed for PTSD sleep issues; however, it's most common side effect is vivid dreaming, and that's generally not good if you are dealing with nightmares. If it's recommended, you should specifically ask about that side effect.
Seroquel can create a deep sleep and have the added benefits of reducing overall daytime anxiety; however, combined with effexor you are potentially going to get a bigger 'drug hangover', and have trouble getting going in the morning.
Gabapentin can be great for sleep - I'm not sure if it combines well with naltrexone, though. Gabapentin actually has some popularity as a street drug in high doses, and I don't know that it would make sense for someone with an addiction history to turn in that direction for sleep, specifically - especially if you don't have any of the other issues that gabapentin is used for (neuropathic pain, restless leg syndrome).
While I know you said you weren't dealing with insomnia - the depth/quality of the sleep we get is what (most likely) influences whether or not we remember what we dream, and how far into the deep-dreaming phase of sleep we go. For me personally, my nightmares were very related to flashbacks - and so, it turned out that I needed to find the med that was going to help me sleep more deeply and make it harder for me to just jolt out of sleep. I think that's common for many people. But, sleep/dreams are still not thoroughly understood.
What are you doing for therapy? Managing the flashbacks will rely more on cognitive intervention for you, probably - the drugs generally prescribed to help with them are all in the benzo class, and depending on your specific addiction history, might not be advisable.