"The Messenger of Allah was asked about prostatic fluid and he said: 'For that ablution (is necessary), and for semen, bath is necessary.'"  

سُئِلَ رَسُولُ اللَّهِ ﷺ عَنِ الْمَذْىِ فَقَالَ فِيهِ الْوُضُوءُ وَفِي الْمَنِيِّ الْغُسْلُ  

He asked the Prophet about a man who approached his wife, but did not ejaculate. He said: "If anyone of you finds that, he should sprinkle water over his private part (meaning he must wash it) and perform ablution."  

أَنَّهُ سَأَلَ النَّبِيَّ ﷺ عَنِ الرَّجُلِ يَدْنُو مِنِ امْرَأَتِهِ فَلاَ يُنْزِلُ قَالَ إِذَا وَجَدَ أَحَدُكُمْ ذَلِكَ فَلْيَنْضِحْ فَرْجَهُ يَعْنِي لِيَغْسِلْهُ وَيَتَوَضَّأْ  

"I used to suffer from a great deal of prostatic fluid, and I took many baths because of that. I asked the messenger of Allah about that, and he said: 'Ablution is sufficient for you in this case.' I said: 'O Messenger of Allah! What about the prostatic fluid that gets onto my clothes?' he said: 'it is sufficient for you to pour a handful of water on the part of your clothes wherever you see it has reached.'"  

كُنْتُ أَلْقَى مِنَ الْمَذْىِ شِدَّةً فَأُكْثِرُ مِنْهُ الاِغْتِسَالَ فَسَأَلْتُ رَسُولَ اللَّهِ ﷺ فَقَالَ إِنَّمَا يُجْزِيكَ مِنْ ذَلِكَ الْوُضُوءُ قُلْتُ يَا رَسُولَ اللَّهِ كَيْفَ بِمَا يُصِيبُ ثَوْبِي قَالَ إِنَّمَا يَكْفِيكَ كَفٌّ مِنْ مَاءٍ تَنْضِحُ بِهِ مِنْ ثَوْبِكَ حَيْثُ تَرَى أَنَّهُ أَصَابَ  

He came to Ubayy bin Ka'b accompanied by 'Umar. Ubayy came out to them and said: "I noticed some prostatic fluid, so I washed my penis and performed ablution. 'Umar said: "Is that sufficient?" He said: "Yes." He ('Umar) asked: "Did you hear that from the messenger of Allah?" He said: "Yes."  

إِنِّي وَجَدْتُ مَذْيًا فَغَسَلْتُ ذَكَرِي وَتَوَضَّأْتُ فَقَالَ عُمَرُ أَوَ يُجْزِئُ ذَلِكَ قَالَ نَعَمْ قَالَ أَسَمِعْتَهُ مِنْ رَسُولِ اللَّهِ ﷺ قَالَ نَعَمْ