ALLEN PARK — While the injuries aren’t serious, six of the seven Lions who missed Monday’s practice were defensive backs.

“We don’t have anybody that’s more than day to day,’’ coach Jim Schwartz said.

Chris Houston was out due to a migraine headache. He’s suffered from migraines since he was young, it’s a hereditary issue. 

"This has been since I’ve been little, my mother goes through it, my sister goes through it, my aunty — it’s hereditary on my mother’s side,'' Houston said.

He takes Imitrex nasal spray to feel better.

"The quicker I get to my medicine the quicker it goes away,'' Houston said.

Also missing on Monday were Louis Delmas who practices intermittently; safety John Wendling; cornerback Ross Weaver, safety Amari Spievey, cornerback Chris Greenwood and wide receiver Patrick Edwards.

Don Carey has been filling in for Delmas with the first team since training camp started. On Monday, rookie Darius Slay was in for Houston.

“It’s not ideal, you’d like to have continuity at a position but it’s life in the NFL,’’ Schwartz said. “There’s always going to be times where you’re not able to get them all on the field at the same time.’’

That’s especially true with rookies like Slay and also safety Glover Quin, a veteran who has not had much practice time playing with Delmas.

“At some point he’d be good to get all guys on the field together and get some continuity, get some communication,’’ Schwartz said. “They’re all working, they’re all getting equal reps, that can be an issue at times.’’

The Lions added veteran cornerback Myron Lewis who practiced on Sunday and Monday.

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