The discharge that comes out of a man can only be one of three types: 

1 – It may be maniy which comes out with feelings of physical pleasure, whether in a wet dream, when having intercourse or in some other way. This is taahir (pure) and is not naajis (impure). What a person must do in the case is ghusl, because Allaah says (interpretation of the meaning): 

“If you are in a state of Janaaba (i.e. after a sexual discharge), purify yourselves (bathe your whole body)”

[al-Maa'idah 5:6] 

2 – It may be madhiy which is a thin white viscid fluid that comes out when desire is provoked. This is naajis (impure) but its impurity is light and it is sufficient to wash the private parts, and to sprinkle with water whatever gets onto the clothes or body. This breaks one's wudoo’, so one has to do wudoo’ again. 

See al-Lajnah al-Daa’imah, 5/381 

3 – It may be neither of the above, in which case the ruling is the same as the ruling on urine: it is essential to wash off any of it that gets onto one's clothes, and it breaks one wudoo’ so wudoo’ must be repeated. 

See al-Sharh al-Mumti’, 1/280. 

With regard to a person who has the discharge continually, the ruling is the same as the ruling on one who is affected by urinary incontinence, i.e., he must clean himself, and use some kind of protection so that it will not get onto his clothes or contaminate the places where he goes, such as mosques and the like. He should do wudoo’ at the time of each prayer, then do all the acts of worship for which tahaarah (purity) is required all together at that time, until the time ends. So you have to do wudoo’ before doing Tawaaf, then it does not matter what comes out after that. 

The Standing Committee was asked about a man who suffered from urinary incontinence – how should he purify himself for prayer and tawaaf? 

They replied: 

If the situation is as you described, there is nothing wrong with your praying and doing tawaaf even if some urine comes out of you, so long as it is coming out continuously, because you come under the same ruling as those who suffer from incontinence. So you have to wash yourself with water when the time for prayer begins, then do wudoo’ for prayer, after which it will not matter what comes out of you until the time for the next prayer comes. 

Fataawa al-Lajnah al-Daa’imah, 5/408 

And they were asked about a man who passes urine continually and the flow never stops – how should he pray? 

They replied: He should pray according to his situation; he should wash himself with water and do wudoo’ for every prayer when the time for prayer comes, and he has to do what we have mentioned [i.e., using a pad of cotton etc] to prevent the urine getting onto his body or clothes, or soiling the mosque. 

Fataawa al-Lajnah al-Daa’imah, 5/507.