Yes. I believe the reason this is happening is because we treat our celebrities like they are better than the rest of the population. Because of this, there is nobody in their circles who will tell them no. The people around them have a fear of being kicked out of the "inner circle" of even disowned, in the case of the circle containing relatives. People will sometimes do whatever is necessary, in their view, to ensure they keep getting a piece of the pie.
I do not believe that drug overdoses among celebrities are increasing, it is just that with our media saturation and the openness of information that is spread throughout the world with such ease, we are just more aware of the private matters of certain individuals. So no, it is not increasing.
I do not believe that drug overdoses are increasing among celebrities. Celebrities live with the unfortunate burden of having their personal lives publicized relentlessly by the media and the information advertised to the general public is most often hearsay. Furthermore, even If one were to assume that all overdose cases were in fact the truth, it would not be difficult to see that these constitute a small minority of celebrities. At times there are certain individuals that will overdose multiple times over a period of time, contributing to the notion that overdoses are increasing.
In my opinion, drug over doses are unfortunately certainly increasing but no more in celebrities than they are in the general population. We may assume they are on the rise among celebrities but I feel that is just because the celebrities happen to be highlighted and reported on due to their fame.