Hi Dinesh,
I understand your concern, but there is no specific treatment for
dengue, and no actual way to force the platelets up. The platelets will recover on their own once the dengue passes.
What helps at this point is making sure he is not dehydrated, because this is the critical stage when the fluid starts leaking out of his blood vessels. At a platelet level of 75,000 he should be in the hospital to be monitored, make sure you get him admitted if he isn't already so.
Make sure the doctors are fully aware of any background health problems he has, because it helps them in adjusting the intravenous fluids they give him. It also makes them more prepared with handling him in the recovery phase, where he might be overloaded with fluids.
If you can't get him admitted for whatever reason, try to get him to take 2-3 litres of isotonic fluids for another 1-2 days or so until he feels better, unless he has other health conditions that requires him to limit fluids like
heart failure or
kidney failure. Make sure he goes for daily (more frequent if it drops further) blood counts to monitor the platelets and haematocrit, which will tell us which stage of the dengue he is in.
Hope this helps, and all the best to your father.
Regards,
Dr. Teh