It depends on tolerance in my opinion. I have run clen, caffeine, ephedra, dmaa in the same day. Clen was in morning. The rest were for second workout. I had no issues but I also use responsible doses. If you are the kind of person that thinks more is better I would not suggest it. Low dose worked just fine.

The only advice I give on stacking Clen is stack it in the trash can... If your not careful it will ruin you...

Albuterol inhaler would be better (safer) option.
It's Fast acting And I think it stays in your system about 30minutes.
3000mg l carnitine 15min before cardio
2,3 shots of Albuterol right before cardio, plus couple more during cardio
30 min of cardio on empty stomach with above combo will get you shredded safely.

NO other forms of stimulants should be used while using clen.

Its just not needed with CLENBUTEROL in my opinion.

I seen the title and thought, BAD IDEA

Do yourself a favor get your diet in chevk and forget the clen !! Clen is to hard on the heart cause heart valve issues.. And 99% of the time U gain the weight back cause your diet isn't disiplined enough

In my experiences with clen, I definitely would not add anything to it. Made my heart contractions VERY strong. No preworkouts, no coffee, no energy drinks.

I don't know if it would have any added benefit synergistically or not.