My father is in stage 2 Parkinson's disease. Recently, he tried to take his life by taking a combination of prescription sleep aid medications - he did not succeed. He has trouble walking, can't sleep, is constipated, has heart disease, urinary problems, etc. Now he is also on anti-depressant medication. He lives with my mother but we see them every day. What can I do to help him? How can I be sure he does not try to take his life again?
Based on all my research, depression, anxiety and apathy are very common with PD. Although the apathy that now grips my mother is often very frustrating for my father and I, it seems to be a blessing in disguise for my mother, somewhat protecting her emotionally from the disease progression and my father's constant complaining and nasty temper.
Now specifically addressing your questions, the best things that you can do, speaking from personal experience, are as follows:
(1) Make sure that your father is taking his PD medications consistently and timely since almost all PWP (people with PD) share an eventual inability to do this correctly, although it's SOOO critical for them. This becomes more and more critical as the disease advances. I'm glad that your mother is now managing this. Also, it's critical that the anti-depressant that your father takes is compatible with his PD meds. It, too, may need to be increased, even if only for a while to get him through this current bout of depression.
(2) Attend periodic appointments with your father's neurologist (or other PD specialist) to stay current, provide input, and receive info. Your attendance lets your father's physician know that you are an integral part of the care team and your input to your father, as part of his care team, will alleviate some of your parents' concerns as well. To make sure that you are in the loop, have your father sign the requisite paperwork to grant the doctor's office the permission to freely communicate with you about your father.
(2) Watch for physical, mental and emotional declines since they may be indicative of a need to adjust or even change PD medications and/or anti-depressant(s).
(3) Encourage both parents to remain socially and physically active. Once they become inactive, it's almost impossible (in my experience) to get them to regain even a little bit of their former activities.
(4) Watch out for exhaustion and caregiver burn-out on the part of your mother; she, too, can end up in trouble.
(5) Continue to stay present in your parents' lives and maintain or, if you don't already have it, develop open, trusting, and hopeful/positive communication so you can gauge their needs, help them personally or assist with the hiring of someone to help them as needed, and compassionately guide them toward making plans for the future with respect to third-party in-home care, possible assisted living and eventual skilled-nursing needs, etc. (This includes researching care services and nursing facilities on your own if your parents, like mine, stubbornly refuse to make preparations.)
(6) Lastly, regularly remind your parents that you love them and are there for them. That will ease some of their anxiety and fears. Also, take your father out of the home for a periodic father-daughter outing for something he enjoys doing (great distraction and mood-lifter, even if temporary) and, also, to give your mother some much-needed time to herself. (My mother-daughter outings nowadays are not only enjoyable for us both but also healing for my "inner child" since my mother never took me on such outings when I was young.)
In conclusion, there's a lot more that I could write, but these are the biggies, I believe. All this being said, none of this is easy on you either. In addition to dealing with your parents' issues, you, like I, are surely struggling with issues related to your father's PD. Please take care of yourself so you remain strong and healthy in all ways physical, mental, emotional and spiritual. As this disease progresses and especially if cognitive decline (e.g., PD Dementia becomes a part of the equation, as it does for many elderly PWP in the later stages, including my mother, although, very early on in the disease for her), your parents will rely on you more and more (willingly in some ways, hesitantly and even begrudgingly in others), and you want to make sure that you are able to be there for them and strong enough to handle what lies ahead. I'll gladly provide more input, support, etc. if you're interested, whether via this discussion or on a one-on-one. I wish you and your family all the best on this long journey, mostly love and compassion for one another.