The patients,

Patients appear to be amalgamations of human remains and artificial mannequin parts. Just as any other residents, they are much larger and taller than the protagonists of the game, they vary greatly in appearance and size, from full bodied bandaged human heads and torsos with prosthetic limbs, to scuttling rotten hands. The larger Patients are three times the height of Mono and Six. Most of them appear to be wearing the same set of clothing.

Apart from the basic prosthetic hands and feet equipped by the majority of Patients, many Patients can additionally wield a variety of unique parts: grappler arm hooks, metal peg legs, and incomplete facial prosthetics. Some Patients lack a few prosthetics on their body, ranging from missing hands, arms, legs, to even their entire head. Few of them are completely limbless but still active. The Patients' prosthetics seem to be made of plastic or wood, with metal joints to link limb and facial sections in place, giving them a rather weak structure with their actual weight centering around their torsos. The Playstation Blog sheds some light on the Patients' past. The Patients were actually people who came to the Doctor for "a medical solution to the boredom infecting their lives." The Doctor stitched various organic and porcelain body parts together, to create the Patients as we see them now Although there are a lot of Patients seen throughout the Hospital, only a small percentage that are encountered by Mono are active.

After Six gives a boost for Mono to start a journey for the second fuse for the main elevator, a Patient will be seen blocking the bars. Mono has to distract it out of the way by turning the lights off. Not long after, he encounters more of them in a ward.

Later, several Patient arms burst through numerous cell doors in a corridor. Mono has to avoid these arms and keep moving forward. Afterward, some Patients with no legs break out of the doors and pursue Mono. Mono manages to escape them by climbing up a cabinet file, entering the vent above to arrive in a shower room.

In the shower room, Mono encounters a Patient sitting on a wheelchair, its weight making the chair immovable. Mono is able to get the Patient to move away by turning off the lights, luring it into the shower room. Mono turns the light back on to freeze the Patient. Before finally finding the second fuse, Mono is faced with a large dark room filled with countless Patients, about half of which become active. Mono eventually makes it to the other end of the room where a set of nailed wood boards barricade Mono from the hostile Patients, who begin reaching at him through the gaps.

After taking the elevator down, numerous inactive Patients are found being littered around the morgue and some being operated and checked on by The Doctor. A still-breathing Patient is seen when Mono and Six try to stay unseen by the Doctor while trying to obtain a fuse. However, Mono has to shut down its life support to distract the Doctor.

Following the final encounter with the Doctor, Mono and Six at last escape the hospital through the waiting room, where the duo encounter numerous inactive Patients waiting around one final time. Some Patients can chase Mono (and Six), but only in the dark. Mono can either direct the flashlight at them to freeze them, or lure them to an external light source or a dead end, allowing Mono to escape through narrow gaps. If they catch up with Mono, they will not hesitate to reach and grab him, which will result in a game over.

Players normally do not have to worry about any pursuing Patients breaking obstacles or wooden barricades, as their weak structures are not powerful enough to push through them.

It may also be worth noting that some Patients sprint while others walk more sluggishly. The latter moves at about the speed of Mono's run, have a harder time turning or maneuvering around obstacles and can even be dodged if they reach to grab Mono (though doing so is still highly difficult). Patients that sprint can be identified by being more hunched over when active while Patients that merely walk have a more straightened posture. Although some Patients do not posses leg prosthetics, they are still capable of crawling at a fast pace using their hands alone. In the attic of the Hunter's shack, a number of prosthetics can be found. These prosthetics are similar to the ones the Doctor uses to "heal" Patients all throughout the hospital. After dealing with the first Patient and arriving at the hallway, there will be a visible limbless patient on a shelf. If Mono climbs onto the shelf and stands beside the body, the body will suddenly wiggle around loudly, causing a jump-scare to those who aren't aware. After Mono escapes several of the Patients, their arms will reach out of the boarded up doorway he used to escape. Mono can find a ball in the room where the chase ends and throw it at the Patients arms, which they will catch and throw back. Mono can do this over and over, similar to a game of catch. This will earn the player an achievement. In the pre-launch trailer for Little Nightmares II, one of the Patients moves without any problems and tries to get out of bed, despite being exposed to light from the window. It is likely that at that time the mechanics of using light against Patients had not yet been invented and developed. One of the Doctor's Patients is shown to still be breathing, laying on a bed with life support activated. Originally, there were going to be younger-aged Patients according to concept arts. Parts of the Patients prosthetics can be identified within the ashes of a cremator, implying that the Doctor may discard failed experimental bodies in a crematory machine. None of the Patients retain their biological hands and feet. All the Patient's limbs are reattached with prosthetics. Only the corpses spotted throughout the hospital still retain biological limbs, as evident by their intact feet. The Patients share the same theme with The Man in the Purple Suit and The Dummy from The Sounds of Nightmares, that being Still Life.