A year of "hell" in hospital battling deep depression will be depicted in the new exhibition by one of Scotland's most popular artists.

Peter Howson endured a dark 2012 as he spent the majority of the year in various Glasgow hospitals being treated for severe depression and other ailments, before finally being discharged around Christmas.

Now the painter, whose muscular and often religious works are still keenly collected, is ready to exhibit his new work at the Maclaurin Art Gallery in Ayr, close to where he grew up in Prestwick.

Howson said: "Now that year feels like a million years ago, like it is a lifetime ago. It feels that God was with me, even though I thought I was abandoned. It has made me stronger, to prepare for things to come, so I am a lot stronger now.

"My ex-wife Teri says that I am now behaving like I did before I went to Bosnia as the official war artist: which is 'annoying, cheeky, but happy'.

"I am happy now. Teri said when I came back from Bosnia [in 1993], that's when I changed. I never really got the right treatment."

The artist added: "When I got out from the Western [Infirmary], I just got steadily better. I took myself off the drugs – I just decided to take myself off them, and it's made a huge difference already – I have steadily got better. Everyone is saying 'be careful, be careful' but it is not going to happen to me again.

"What John Bellany [the painter] was saying about being in depression like being in hell: it is, but once you are out of hell, that's it – you might have another depressive episode at some point in your life, but I know what the triggers are, and I know myself a lot better now.

"Some of the exhibition is hopeful new stuff, a touch of humour. And some of it is the mad stuff from Gartnavel [General Hospital], with hundreds of figures. They kept telling me to go back to bed, but I would just pretend to, and carry on working."

The new show entitled From Death To Life runs from March 3 to April 14. It is a mixture of his frenzied works from hospital, many of them drawn during the night at Gartnavel Hospital, as well as pastel and larger oil works.

Ann Bontke, exhibitions supervisor at the Maclaurin, said she is struck by the optimistic and hopeful nature of the new work.

Howson credits the staunch support and care of his assistant, Douglas McDonald, as well as the support of Teri and his daughter Lucie as being critical in his recovery.

He said: "I didn't have time to do a new show with new oils, so there's not very many oils. But what I did do is that the first time I was in Gartnavel, I did about 150 drawings, which I have managed to work on steadily.

"So there is mixture of the stuff I did in hospital and the brand new stuff, which is a lot more hopeful, slightly humorous maybe, and some Robert Burns imagery, mainly from Holy Willie's Prayer, because that is my favourite. Some of the Gartnavel stuff is pretty crazy really."

Howson has previously credited his legal guardians, who monitor his health and finances, with keeping his previously chaotic life in some kind of equilibrium. The painter, who lives and works in Glasgow, said he is not sure the medical attention he received last year is the reason for his recovery.

He said: "I am better now. But I don't think it was hospital that made me better. I think the biggest influence was Douglas who came to visit me every single day without fail, and my ex-wife Teri and my daughter Lucie. Teri gave me a huge amount of emotional support. I was on a huge amount of drugs, which I have managed to come off, apart from one.

"I am working all hours again, but I am enjoying myself, and having fun, and loving life again. I think if it hadn't been for Douglas I would have been a goner."

He is now working on a major religious commission for a private collector as well as forthcoming shows at the Scottish Gallery in Edinburgh and Flowers in London.

Howson added: "I wouldn't say I am painting for survival, but I have wasted a year-and-a-quarter and I haven't made anything. I know that I have to do some work.

"I can concentrate more and I can see and I have more of a vision of what I want to do. I still have problems, but I feel I can take them on now."