Gold Coast trainer Marcus Wilson has had his penalty on cobalt charges increased after an internal review.

Wilson pleaded guilty to two charges of bringing a horse to a racecourse with a prohibited substance and was last month disqualified for a period of 12 months on each charge to be served concurrently.

Wilson sought an internal review of the penalty only and the reviewer, Kane Ashby, amended the original decision in a judgment handed down last week.

"....in considering all the relevant facts (the reviewer) amends the original penalty to a disqualification of 12 months on each charge, with six months to be served concurrently, resulting in a total period of 18 months disqualification," Ashby wrote.

The Wilson-trained Steering was found to have cobalt above the permitted threshold in a post-race urine sample after running at the Gold Coast Turf Club on November 19 while stablemate Lyra was also above the level in a swab taken at Ipswich on December 16.

Wilson will now take his case for further appeal to the Queensland Civil and Administrative Tribunal.