My older sister's been diagnosed with Type I Schizophrenia at February and has been taking her pills since. But recently shes convinced that she's gotten better (like completely) and refuses to take them because the side effects. 

She went to a check up with our local psychiatrist(?Is that the one who gives pills I dont remember) and told her doctor that she doesn't need to take it anymore. 

And the doctor said that she doesn't know what's going on in her brain so she took her off of her pills. 

I've been trying to find answers to help convince her but everything has been about not being able to do anything. 

I'm scared my sister will get worse. The quarantine is happening so we can't take her out as much as often. My parents are under so much stress that they can only get angry at her and yell at her (which I believe makes it worse). 

She gave back her remaining pills this appointment and now the only way to get her back on the pills is to get her to go back and ask for them. 

Any way to convince her?