In 25 years, Comic Relief and its famous Red Nose have helped to raise £600million which has been used to help millions of people both in the UK and Africa. On a trip to Ghana earlier this year I met some of the most recent beneficiaries, as the country struggles to address growing need for psychiatric services.

It is hard enough campaigning for mental health services in the UK, where the government's austerity programme means they are going to the back of the queue again, as psychiatric care is not quite as 'sexy' as cancer, children's services or even accident and emergency. Recently I protested that two of the four emergency centres in Camden, North London, where I live, are closing. But compare and contrast with a country of 25million people, which has just three psychiatric hospitals, and just a dozen trained psychiatrists compared with 46,000 'traditional healers.'

That country is Ghana, in so many other ways one of Africa's success stories. But they know that when it comes to looking after the most vulnerable people in their midst, they have a long way to go. On the day I visited one of those three hospitals, Accra psychiatric hospital, it was impossible to be anything other than shocked, but also in awe of the handful of doctors and the smartly dressed nurses doing their best in difficult circumstances. A children's ward largely made up of mute, seriously disturbed youngsters, some of them dumped on the doorstep by their parents. A men's ward where dozens of 'ordinary' patients mingled with dozens more sent by the courts for assessment, one of whom had been there since the '80s on a murder charge. A women's ward where new admissions mixed with women, some naked, others aggressive - there had been a murder three days earlier - for whom the hospital was likely to be 'home' for years to come.

Even using words like 'ward' risks giving an inaccurate picture. To a Western mind that conjures up shiny floors, beds with sheets and pillows, and machines humming. There was none of that. There were hundreds of patients and small teams of nurses doing their best to look after them. There seemed to be enough medication, but it was hard to imagine how the doctors and nurses could do much more than sedate and calm. On the day we were there, chief psychiatrist Dr Akwasi Osei, said he and a colleague might see as many as 75 patients individually, in between actually running the place, and acting as an advisor to the government. At a second of the three hospitals, Pantang, Polish-born doctor Anna Puklo-Dzadey, with 300 inpatients and around 100 outpatients daily, said they ran to stand still. 'It is hard to do more than that.'

But the government is trying to move in the right direction. They have passed a Mental Health Act, which both Dr Osei and Dr Puklo-Dzadey say has the potential to transform services. 'Implement the Act, implement the Act, implement the Act,' says Dr Osei when I ask what one thing could make the most difference. Dr Puklo-Dzadey says 'the Act is a great thing in that it shows they understand the need for change. But without the resources to make the change real, we will continue to run to stand still.'

The scale of the challenge, not just in terms of the services, but also attitudes, can hardly be overstated. 'Even some doctors believe mental illness is contagious,' says Peter Badimak Yaro, director of the mental health charity Basic Needs Ghana, 'or caused by witchcraft, or sins in a past life. The reason there are so many traditional headers and so few real psychiatrists is that those attitudes are deep rooted in some parts of the country.'

At a Basic Needs self-help group for mentally ill women in Nima, Accra, we hear from schizophrenics who say they are shunned, and epileptics who say their problems are exacerbated by the fact that many think if you touch an epileptic, you will catch the illness. One after another, the women explain how the self-help group has given them a support network they lacked before. 'We look out for each other, make sure we take our medication, feel stronger for knowing there are other people in the same situation,' said Leyla Suraka, 53, a schizophrenic who went ten years without treatment.

Several have stories of the so-called prayer camps, where instead of medication and therapy, treatment is often made up of beatings, fasting, exorcisms and being tied to tree trunks to prevent escape. It will be hard to break down the attitudes, but again, the government is trying. Nana Oye Lithur, a human rights campaigner, has been appointed by the new president to a new position of minister for gender, children and social protection. She intends, as part of the social protection brief, to ensure the prayer camps are properly regulated and inspected.

'Mental health has been neglected,' she says. 'The stigma and discrimination prevent people from accessing proper care. It will take time to turn it round, but we can.'

The small beginnings of one self-help group have now grown. There are 193 of them. Eight drama groups perform plays about the main mental illness to dispel some of the myths. But Basic Needs Ghana also provide direct support for the medical services people require, with more than 20,000 people having benefited from their work. I spent a morning at a polyclinic where men, women and children queued in the heat to see two nurses. It is basic care, but it is care nonetheless.

As to what this has to do with the good people of Britain, the answer is simple - you help to pay for it. Basic Needs Ghana, and the Mental Health Society of Ghana, are part funded by Comic Relief. As Red Nose Day comes around again, there will be the usual mix of extraordinary generosity, and cynicism about whether the money actually does any good. Compassion fatigue is perhaps inevitable when so many give so much to so many causes. But if anyone reading this feels the compassion fatigue setting in as the Red Nose films come across their screens, try to remember people like Memunata Sale, who was given money for a sewing machine so she could make clothes and earn what she needs to look after her sick father. People like Asibi Nabase, 39, who is visibly ill, but whose mother says she finds sanctuary in the self-help group meetings. People like Ernest Appiah, 38, who was rescued from a prayer camp, treated by nurses, and now has a job in a bank. People like Dickson Dorcoo, 63, suicidally depressive and so ashamed of mental illness that his wife felt she had to hide him away until she heard about the polyclinic. People like Sahara Jubila, 30, who needs regular medication to live sufficiently well with her schizophrenia to be able to look after her eight children, People like Leyla, in and out of hospital for years, but who has not been back for five years. People like Francis Pii Kugbila, who was chained to a tree for two years until Basic Needs Ghana found him, and is now back at work as a teacher. So think of the children he is teaching too.

Things are in Ghana - indeed across Africa - are changing for the better and not just with regards to mental health. Access to education, clean water and mosquito nets are all making fundamental differences to the way millions of people live. As Red Nose Day marks its 25th year, I've seen the good work that is being done with the money it raises. There is still a long way to go, but Pii now has a future to look forward to, partly in thanks to someone donning a red nose or wearing pyjamas to work.

Alastair Campbell is an ambassador for the Time to Change campaign.

Red Nose Day is back on BBC One on Friday 15 March, tune in from 7pm to watch Comic Relief - Funny for Money. To find out more go to rednoseday.com

Follow Alastair Campbell on Twitter: www.twitter.com/campbellclaret