something to add

leslie3456​ Sims can indeed get sick and purchase medicine from the computer or phone (with Seasons telephone gift purchases) to cure themselves. I believe this was added with the Get to Work pack. I don't think it's base game but could be wrong as it's been a part of my game for so long. My Sims are sick way too often actually and it can take a couple of doses of medicine to recover. They can also drink orange juice and brew tea to feel better.

They can also get sick from eating spoiled food or if a vegetarian Sim eats meat or a mermaid or Child of the Ocean (with Island Living) eats fish. Or a pregnant Sim can have sickness too.

Get to Work also adds various illnesses for the active medical career that Sims can diagnose and treat at the hospital during the work day. They include Sweaty Shivers, Gas and Giggles, Llama Flu, Bloaty Head, Burnin Belly, Itchy Plumbob, Starry Eyes and Triple Threat. They can require medication, a shot or even surgery. If I'm playing the medical career I always hate to see any of my played Sims at the hospital reception and I feel the pressure to get their diagnosis and treatment right... especially for my little child Sims! 🥺

Oh my! You've convinced me to try the medical career with one of my sims. It's one of the careers still on my to do list 

Sims can get sick but to me it's not realistic like I want the option to go to the hospital or doctor just like a pregnant sim get cured or get a doctor's note saying you'll be out for a day or two it can even be a rabbit hole doctor appointment but I would to hear Sims cough and sneeze. 

Totly agree more realism like getting sick would add depth. I get creative ideas from sites like krydsordfinder too!

I also agree with you in that I'm 99.99% sure that illness came with Get to Work and isn't a base game thing.  But like you, I also have played this game so long, and got GTW when it was first released, so it is hard to separate which came with the pack and which is from the base game. 😅  But further evidence that illness was an addition with GTW and not base game is that I've seen many people over the years wonder why Sims don't get sick, which they would if this was a base game gameplay feature.  😉

I was always surprised if my Sims' rash would change! For example, my Sim might start out with a striped rash, but then it changes to a swirly rash, or a dotty rash! 😅

simsplayer818​  Think that's tough? My doctor sim's father actually stumbled into the hospital reception area and collapsed in front of her. She had to rush him to surgery. It was quite a shock.

i created this post awhile baack and it involves getting sick and going to the hospital

my idea match with "Get To Work" refresh perfectly but knowing EA these days, they'll make new packs rather than refresh them

Sims 4 Hospital Health Expansion Pack idea | EA Forums - 12150457