Absolutely not. Leavin conditioners are al ways light as to not to weight your hair down without washing it out. Deep conditioning is a heavy conditioner designed to intensely repair your hair. You can leave it in all night, in fact i recommend that. But you always wash it out the next morning.

Try redken leave in extreme force rescue conditioner as a deep conditioning treatment
http://www.twenga.com/dir-Health-Beauty,Hair-care,Hair-treatment-8922

Or revlon bi-phase for a leave in
http://www.priceminister.com/offer/buy/47847355/Revlon-Equave-2-Phase-Soin-beaute.html

first off, deep conditioners would never make your hair fall out. that type of thng only happens with products that have lye in them, such as perms or relaxers.

now, to answer your question more thoroughly, it depends on your hair type if your have curly hair or coarse hair then yes. if yu have fair hair then heck no. dconditionersners are really concentrated. that means if you have fair hair then it will burn your hair. but if your hair is super dry like curly hair or your strands are thick like coarse hair then the pros outweight the cons. if i were you, i would just lightly water down the deep conditioner. now you are good to go.