This is still registered medication ?
Well, ok.
It was poor attempt for treating generalised anxiety disorder.
It's of 0 use for any disease as a single, main psychoactive medication but it won't harm ( probably the opposite ) when used in therapeutic doses as an adjunct medication for treatment of opioid WD, depression, anxiety.
In low doses it even enhances dopaminergic and noradrenergic transmission in some parts of your brain.
But in middle to high doses it Is very, very mild antipsychotic ( no usual negative effects of casual antipsychotics ).
Instead they used it as a delayed-onset anxiolytic which means that in timeframe of 2-6 weeks it should help with symptoms of anxiety (only GAD), by letting your serotonine and dopamine receptors agonised, partly agonised, antagonised for example it will help revire your dopamine receptors throught very mild dopamine antagonism.
I would use Hydroxizine 25-100mg ( CNS anxiolytic, antihistamine, antinausea and mild sedative ) + buspirone 10mg 3x per day ( CNS monoaminergic mixed agonist-antagonist ) + clonidine or tizanidine as a mixture of nonnarcotic drugs to greatly help with many opioid WD symptoms. If u add loperamide in therapeutic doses u should't even need anything addictive or hard to be prescribed ( benzos, pregabalin, gabapentin, other prescription only sedatives ).
One thing i would do, Is start treatment with one of more effective antidepressants, if u never used them try 5mg escitalopram / 10mg vortioxetine ( both non sedating and both potent when they finally kick in, vortioxetine is mainly for people who doesn't respond to classic SSRi, SNRi,NDRi but if possible i would choose it right from the beginning because in 20mg dose it doesn't raise serotonine to the extreme level but instead only +- 65% serotonine increase, noradrenaline + dopamine increase - it Is like activating and cognitive-enhancing atypical antidepressant drug ) with addition of 15mg mirtazapine as your evening add-on hypnotic antidepressant medication and trust me, Mirtazapine + Hydroxizine + tizanidine = heavy sedation, anxiolysis and mood elevation , + loperamide for all PNS opioid WD symptoms reduction, + daytime vortioxetine or escitalopram boosted by buspirone and your WD will be much less severe in symptoms and at the same time u will not only complete WD from opioid but also revire your CNS, give a little rest for repairment of many pathways drained from excessive dopamine and serotonine release caused by opioid-agonist dependence, and 14 days since start of this WD treatment u will also be ready for PAWS cause, u will be on 2 antidepressants, additive anxiolytics and your sleep patterns would be improved greatly, mirtazapine Is perfect for sleep improvement ( acute hypnotic ) and also strong sedative and AD if u decide to take it even after the first 14-30 days.
Wish u good luck.