Trying this for the second time with a lot higher dose and I am also IVing ((best way to do it with the right size micron filter) )
You absolutely should not inject this drug, even if you have micron filters. It is among a short-list of drugs that cause complication at a rate and intensity higher than other drugs; even other pills. Buprenorphine, for instance, is known to cause more complications per capita than a lot of other drugs.
(Dex)Methylphenidate, whether it's Ritalin or Focalin, is also well-known to cause complications at a very high rate. In most other cases, I wouldn't say anything, but this is an outright dangerous practice that needs to be addressed with HR in mind. It's something that cannot be done with any confidence, even in the best of circumstances. Why do you need to do this?
Heroin users begin injecting for financial reasons. We get sick, we get at least double our money if we inject. Sure it feels good too, but this is why addicts eventually end up on the needle. You don't have any kind of fire under your ass that predicates you using this drug in this manner. You get a small rush, sure, but is that worth an abscess? Methylphenidate has a reasonable bioavailability anyway. It's not the best, but it does not mean you need to IV.
I'm not judging you at all man. I've done dangerous things in my life too. I'm just hoping to prevent people from making the same mistakes without patronizing them, which is quite a tight-rope to walk for us. I just want you to be safe man.