The 24-year-old sustained a facial injury during last Saturday's Test against South Africa at Murrayfield which forced him to retire early from the match.
The injury was described as "unusual and complex" by Scotland doctor James Robson on Tuesday, amid fears Callam would have to withdraw from Frank Hadden's 30-man squad.
But there was relief all round this morning when expert medical advice cleared Callam to make the trip to France with Scotland in seven days' time.
Robson said: "After further consultation yesterday with another specialist, Dave Callam has been cleared to resume light training with the Scotland squad on Thursday with a view to a full bill of health from Monday.
"The ophthalmologist found his vision unimpaired and the facial surgeon he saw yesterday has passed him fit to resume light training this week."
The Edinburgh back-row forward took a blow to the area immediately above his right eye in the clash with the Springboks.
It was thought to have been an accidental clash of heads but it meant Callam subsequently suffered blurring to his vision.
Callam said: "I'm obviously very pleased and keen to get back into action."