CBD is amazing. I don't think your doctor isn't helping you there with their recommendation; against taking it.

I've tried 8+ anti-depressants. Been on Benzodiazepines for over 7 years. Tried every recreational drug most people have even heard of, and more.
CBD is the only thing that has actually made me 99% free of physical anxiety.
It works very well on the mental aspect of anxiety too.
I vaporized it. It's much more effective than orally taking it. Sublingual (under the tongue) is the best alternative to vaporising it.

Ask your doctor if they forsee any medication interaction / side-effects. Maybe a different doctor or, at least ask why they think it won't help.
For anxiety - CBD is the best thing i've found in 15 years of searching. It annoys me that a G.P wouldn't recommend it for anxiety.
I would certainly recommend you it. I believe it'll help massively - both with mental anxiety, and the physical effects anxiety has on the body.

Get a good brand. The difference is night and day between brands as it's an unregulated industry.
I have OCPD and OCD - I am good at research.... after 14hours researching I settled on this brand:
CBDDistillery. Here's the U.Ks official distributor;
Hempbotanics.com

Side-effects wise - CBD has dry mouth, and I believe it can lower blood pressure slightly.
One of the main side-effects with Bupropion is it makes you more likely to have seizures (lowers seizure threshold).... - CBD has an anti-seizure effect. so I can't personally see CBD being a problem. (I have no medical certification or training) Do ask a doctor however.
Has bupropion been helping? I remember reading one of the side-effects is anxiety.

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It really is superb CBD. Full-spectrum is better imo. (CBDDistillerry have pure CBD and Full-spectrum CBD)