Is it possible you're herxing with the mass worm die off and their toxins. That's my guess. I think your pulsing is just managing the die off.
If were allergic, you wouldn't be able to take it at all.
In the next week or two when the die off is less, you probably should follow ICU's protocol which includes both ivermectin and albendazole, and possibly at a later time, switch to just ivermectin. But take as directed so your parasites won't become resistant to the med.
Glad you finally found the problem. I also have strongyloides which I believe have been latent for about 55 years. They say the record is 65 years.
Here is a link re. strongyloides which I thought was good.