Negative Ions

Negative Ions are a liquid-type spray of ions used in Mario & Luigi: Bowser's Inside Story. Being the equivalent of Mushroom Tea and Emoglobin Sweat that Mario and Luigi use, it fully restores Bowser's HP and SP. For Bowser to obtain a blast of ion mist, he has to go to a Shop Block, managed by Broque Monsieur, and punch it. Each spray costs ten Coins. Bowser is able to use Negative Ions whenever he comes to a Shop Block, and it can still be used even if his stats are already maxed out.

Mario and Luigi cannot activate the Shop Block, since their hammers are not powerful enough to trigger it, meaning that they cannot come in contact with Negative Ions.

Trivia

 * Unlike Mushroom Tea, negative ions will restore both HP and SP without a choice, while Mario and Luigi have the option of healing either SP or HP or both.