Requirements:

JIP LN NVSE
The Mod Configuration Menu
UIO - for the "Info" options under Companion Wheel Integration.

How to Use:

General Use: Once ingame, look at any NPC and hold down the hotkey (by default, "-"). This will open a menu listing all valid aid items (see "Detailed Information" for more info). Once you click on an item, it will be used on the target NPC.

Advanced Hotkeys: Open the MCM and click on "Advanced Hotkeys Setup". Go down to the bottom and click "Add Hotkey". Press the key you would like to use, and once it is added to the menu, click on it and select the item you'd like to use when pressing it. The Combo Hotkey can be set, if desired, to try and prevent any hotkeys set from conflicting with hotkeys from other mods, if you are running short on free ones. After setting it up, all you need to do is look at a NPC and press the key.

Favorites: "Favorite" items can also be set in the MCM. When appropriate, they will be moved to the top of the First Aid menu as they are ordered in the MCM. If Fav #1 is set to Stimpak, #2 to Psycho, and #3 to Super Stimpak, when the First Aid menu is opened on a NPC that is not a companion, #1 and #2 will be Stimpak and Super Stimpak respectively, with the rest of the aid menu being ordered as detailed below.

Companion Wheel Integration: If enabled, the Use Stimpak button will instead open the First Aid menu and the HP/Stimpak counter in the Companion Wheel will be replaced, now showing HP, Status such as if the companion is crippled or poisoned, and SPECIAL stats.

Detailed Information:

General Use:

By default, there are a large amount of restrictions in place if the NPC you are performing First Aid on is not a companion or is a robot.
For everyone, poisons and quest items can not be used. You can't use any items on a hostile NPC.
If they aren't a companion, you can only use medicines on them (Stimpaks, Doctor's Bags, etc). No addict-ables allowed.
If they are a robot, you can't use chems, medicines, or food on them. Some items, such as Stealth Boys, can be used.
The only restriction in place for non-robot companions is it can't be a magazine/skill book. Want to shoot up some Psycho with Boone and Rex? You are of debatable morals, but go for it.

A lot of these restrictions can be enabled or disabled in the MCM.

Items will be sorted with medicines first, then alphabetically.
For example;

Doctor's Bag
RadAway
Stimpak
Brahmin Steak
Psycho
Whiskey

would be a valid list.

Favorites:

Favorites are tied to your save, so any set will only apply for that character. They can also be rearranged or removed individually by selecting them in the MCM.

Companion Wheel Integration:

First Aid NVSE can be set to override the normal information text and function of the "Use Stimpak" section of the companion wheel. These are available separately, so if you want to keep the stimpak-spamability of the default companion wheel but show SPECIAL stats you can.
By default, the companion wheel will now show Hitpoints, Status, and SPECIAL stats.

Status: "Status" is a semi-immersive overview of the NPC's status.
For robots, it will show "Damaged" if they are below 50% HP or have any part crippled, otherwise showing "Functional".
For organics, it is more complex. In descending priority:
If they are poisoned, Poisoned.
If they have 3 or more crippled limbs or are below 25% health, Critical.
If they have any crippled limb, Crippled.
If they are below 75% health, Injured.
Otherwise, Healthy.

Credits:

Axonis - Companion wheel integration idea, UI tips, and some tweaks to what I set up for it.