Having enjoyed a winner aboard 7-2 favourite Reverberation in the apprentice handicap earlier on the card, Ryan was partnering the Luke Comer-trained Guild in the Crowne Plaza Dundalk Race & Stay Handicap when his mount became short of room not long after the stalls opened.
Ryan was catapulted to the ground and was down for some time while being attended to by medics.
The rest of the field went on to complete almost a circuit before the race was called off before the home turn.
The Irish Horseracing Regulatory Board tweeted an update from on-course Dr Antonia Lehane, saying: “Gavin Ryan is fully conscious and talking. He is going to Drogheda Hospital for precautionary x-rays.”
Short-head winner Reverberation was trained by James Lambe, who was full of praise for Ryan – who had a scare when unseated from the 7-2 favourite on the way back to the parade ring after the mile event, but was able to stay on his feet.
Lambe said: “It’s great to get it. He was third here on his last visit and then I sent him to Newcastle and we were disappointed, but I think the straight mile is tough there.
“Going left-handed around two turns here suited. Gavin gave him a great ride.”
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