Pokémon Red and Blue/Items

To access the ITEM GUI, you have to press and click on the ITEMS tab. In other generation, this is called the PACK or the BAG. None of your items are organized at all, unlike future generations. Here's a complete list of all the items in the first generation of Pokémon(note that images of items do not appear in generation one games. However, pokeball sprites do appear and they all look like this.):

Drug Items
''Note: After Generation II, the Stat EXP system changed into the EV system. Stat EXP is similar to EVs.''

Battle Items
''Battle items can only be used in battle, and their changes are temporary. They can not be used if the stat is already raised 6 levels.''

Miscellaneous
''For information about TMs and HMs, visit the Moves section (WIP).