And Smith knows the recent spate of rock musicians’ deaths fuelled the concerns of colleagues, family and fans while the singer received attention for intestinal flu.
Two concerts were called off as a result of Kiedis’ health problems – but the band are set to return to action in Ohio this weekend.
Smith tells Radio X: “His stomach was killing him – it was really scary. We went directly to the hospital. We were really upset we couldn’t play for the fans, but also more worried about him.”
He adds: “I know everyone’s freaked out when they hear about another musician going into the hospital. It’s been such a rough year.
“People sent so much stuff – I really appreciate all the well-wishes. He’s a very strong man and he’ll be back better than ever.”
The Red Hot Chili Peppers’ next performance takes place at Rock On The Range on May 22 (Sunday). They’ll release 11th album The Getaway on June 17.
Red Hot Chili Peppers tour dates 2016
May 22: Columbus Rock On The Range, OH
May 29: Napa Valley BottleRock, CA
Jun 03-05: Nuremberg Rock im Park, Germany
Jun 03-05: Mendig Rock am Ring, Germany
Jun 10-12: Nickelsdorf Nova Rock, Austria
Jun 10-12: Landgraaf Pinkpop Festival, Netherlands
Jun 30-Jul 03: Roskilde Festival, Netherlands
Jun 30-Jul 03: Gdynia Open’er Festival, Poland
Jul 02: Werchter Rock Werchter, Belgium
Jul 09: Moscow Park Live Festival, Russia
Jul 10: Kinross T In The Park, UK
Jul 15: Ottawa Ontario At Bluesfest, ON
Jul 16: Quebec Festival d’ete de Quebec, QC
Jul 22: Jisan valley Rock Festival, South Korea
Jul 29: Osheaga Quebec At Osheaga, QC
Aug 25: Belfast Tennent’s Vital, UK
Aug 26: Reading Festival, UK
Aug 27: Leeds Festival, UK