cat won't stop meowing (a severe case of it)

[val jester]

Hello everybody! : )

My cat is about 8 years old but he’s only been with me for a year now (his former master died).

At first he didn’t meow all that much, but for the last couple of months he started meowing rather histerically from 8 pm to 11 pm, roughly. He cries on the corridor like he’s being hurt or shut somewhere, except he isn’t, of course. He’ll only shut up if I get up and/or go to the kitchen get something done (bizarrely enough, I know).

Then he also wakes me up during the night, usually from 5 am onwards, to get my attention.

Strangely enough from 11 pm onwards he's usally very quiet. Just now I had to check on him to see if he was breathing, as he was sleeping so silently.

I haven't changed my routines and he's apparently in good health, according to the vet and to the state of this fur, eating habits, etc.

Last time I took him to the vet he recommended I bought «tranquilizer» Feliway; for a while maybe that worked, but not anymore.

I need to rest and also I’m afraid my neighbours will complain.

What’s your advice? I do love my cat but everynight he drives me crazy.

Thank you in advance.