A permanently thirsty German architect is forced to drink at least 20 litres of water a day just to stay alive - even though doing so could kill him.

Marc Wübbenhorst suffers from the rare diabetes insipidus which means he always feels thirsty because he urinates excessively.

The 36-year-old's kidneys get rid of the fluids almost as fast as he drinks them which means his body doesn't hold any water.

Mr Wübbenhorst, who works in an architects office, can't even sleep for more than a couple of hours before needing to rehydrate.

If he doesn't, then he experiences the symptoms of extreme dehydration including dizziness and confusion. He can go without water for only an hour.

Drinking excessive amounts of water is dangerous as it can lead to water filling the brain. It has killed a handful of people.

Marc Wübbenhorst suffers from the rare diabetes insipidus which means he always feels thirsty because he urinates excessively

Mr Wübbenhorst, from Bielefeld, said: 'I want people to know about this disability and to get the word out about it. I am thirsty all the time.

'Many people have never heard about it. I have even had doctors who have had to look it up.'

Mr Wübbenhorst spoke about the side effects. He said: 'I wouldn't be able to tell you where I was or understand the question.

'I can drink 22 litres of water a day. I can only go without water for around an hour.

'After that I will have problems with my concentration. I start to get a fever and lose orientation.

Mr Wübbenhorst's condition was spotted by doctors at birth. His mother suffered from the same issue.

However, he is believed to be at constant risk of death from water intoxication, medically known as hyponatremia.

Drinking too much water in a short period of time can cause levels of sodium in the blood to plummet - which can be fatal.

The 36-year-old's kidneys get rid of the fluids almost as fast as he drinks them which means his body doesn't hold any water

Mr Wübbenhorst, who works in an architects office, can't even sleep for more than a couple of hours before needing to rehydrate

A Californian mother-of-three died in 2007 after drinking six litres of water in an hour during a contest to win a gaming console.

If there is an imbalance in sodium levels because of water, then liquid can move into cells and cause them to swell. This is dangerous if it happens in the brain.

WHAT IS DIABETES INSIPIDUS? Diabetes insipidus is a rare condition where you often feel thirsty and often need to urinate. In very severe cases of diabetes insipidus, up to 20 litres of urine can be passed in a day. It is caused by a hormone problem which results in too much water passing from the body. Those with the condition - about one in 25,000 people - compensate for the increased loss of water by increasing the amount of water taken in. Advertisement

Mr Wübbenhorst always has to plan in advance if he travels or is going on a longer journey to ensure that he has enough water.

He said: 'I always carry a bag with bottles of water - that way I can also refill them if I run out.

'From time to time you are left in a tricky position. I was stuck on a train for a long time and I ran out of water.

'That left me dizzy and with a fever. I was eventually helped by someone at the station.'

He added: 'I do horse riding but I can't do sports like football or running as they use a lot of energy.

'Sometime I will have a diet coke or juice but I usually stick to water. For me it is very pleasant to drink it. Obviously sometimes it can be annoying.

'But for me the feeling is like not drinking for two days and then getting to sip some water.'

Mr Wübbenhorst said: 'I can drink alcohol but I don't. Because of the condition I can drink three bottles of wine and it will not affect me.

'I can't sleep overnight for more than two hours. I need to go to the toilet regularly and also have more water.

'If I don't then I get fever dreams. As far as I know this condition is incurable.'