If your test comes back positive and you would be a simple case like tapeworm or threadworm, then I think the medication your doctor may prescribe is effective enough, and you don't have to expect too much discomfort of side effects. It may be different with Ascaris or Strongyloides. I'm not so sure if the usual prescription drugs would be truly effective here - unless you'd take stuff like Ivermectin. While these can be helpful in getting finally rid of the bastards, they are also very strong drugs indeed. And I'm not in the position to tell you that you would be fine/or would get damaged in the process. Humaworm is surely a slower approach, and, depending on how severe the infection is, one course will hardly be enough. Still, I do favour Humaworm because it targets not only your "intestinal criminals", it also helps your organs to deal with the full load of it.
I cannot judge the validity of arguments concerning probable adverse effects of wormwood, my knowledge is simply too limited. I have taken Humaworm several times, and I don't think there was anything in it that would have affected me in a negative way. But that's just me.
If advice from my side is of any value: go with Humaworm first - unless you are in a very bad physical condition related to parasites. Then prescription drugs might be the better (faster) way, but you would need a doctor you have some trust into, and this doctor would have to be willing to check on you every other day for possible severe side effects.
These prescription drugs can be very efficient in killing the parasites targeted in a rather short while. But they usually have a "price-tag" to them. Your digestion or some organs can get pretty much compromised; leaving you feeling as bad as before, despite being rid of the parasites. Then your next move would have to be to re-instate digestion/organ health. That could take a long time to achieve.
I hope this was of a little help to you. All my best. And get well soon, whichever way you choose. :-)