Answer by taking a quote from the following article:

Therapy? are an alternative metal band from Northern Ireland. The band was formed in 1989 by guitarist-vocalist Andy Cairns from Ballyclare and drummer-vocalist Fyfe Ewing from Larne, Northern Ireland. The band initially recorded their first demo with Cairns filling in on bass guitar. To complete the lineup, the band recruited Larne bassist Michael McKeegan.

If there was one true "breakthrough" year in the band's history, it would almost certainly be 1993. The release of the Shortsharpshock EP catapulted Therapy? into the Top 40, peaking at nine, featuring the lead track Screamager. The single led to the first of several appearances on the venerable UK music show Top of the Pops. Two more UK Top 40 EPs Face the Strange and Opal Mantra followed, as the band toured heavily on the European festival circuit, made two separate jaunts to the United States in support of Kings X initially, and then both Helmet and The Jesus Lizard, and played their debut shows in Japan. Compilations of the three EP's were released in the U.S. and Japan (Hats Off to the Insane), and in Europe (Born in a Crash).  1994 saw the release of the commercially successful Troublegum album in February which earned the band appearances at a string of rock and indie festivals, including Reading (third consecutive appearance), Donington and Phoenix in the UK alone, as well as a clutch of Top 40 singles. It achieved a string of nominations in end-of-year polls, including a Mercury Music Prize nomination, and success at the Kerrang! Awards.  With impatience mounting for a new album, Infernal Love was released in June 1995. This time, the press reaction was lukewarm. The band had attempted to create a "cinematic" record with Belfast DJ David Holmes employed to link each track with "insanity", but in the eyes of many, had produced a disjointed piece over-subscribed with ballads. Despite a second consecutive Donington appearance at Metallica's request, and singles Stories and Loose charting in the UK earlier in the year, it was clear that Therapy? had changed direction. Although the string laden single Diane was a Top 10 hit in 15 European countries later in the year, much of the early momentum had gone.

Did they do any songs with other popular artists?
Kings X initially, and then both Helmet and The Jesus Lizard,