TROUBLED AFL star Ben Cousins has been ruled out of Richmond's clash against Fremantle on Saturday, just hours after revealing he had taken ‘‘about double'' the dosage of a prescribed sleeping tablet that sparked his emergency admission to hospital on Monday.

Cousins, 32, trained with the Tigers on Thursday morning at Victoria Park but coach Damien Hardwick said he was not considered for selection.

‘‘He won't play. He has had a far from ideal preparation,'' Hardwick said.

‘‘He has been in intensive care Monday and Tuesday. At Ben's age, a six-day break, been in intensive care, it's not the ideal preparation.

‘‘He will suit up against the Kangaroos in a week's time.''

Hardwick said Cousins, fighting to win a contract for next season, had been desperate to play.

‘‘He is a competitive animal, there is no doubt about that,'' he said.

‘‘He was eager to play, very disappointed when I told him he wasn't going to play.

‘‘But for the good of the Richmond Football Club and good of Ben's health, physically wise, it wasn't a hard decision to make.''

Before training, Cousins, 32, told Melbourne radio station Nova 100 that he had been using sleeping tablets ‘‘for a long time'' but, on Sunday night, had taken pills that were ‘‘not your typical sleeping tablet''.

"I just took the wrong dosage," Cousins said. He denied reports that he had been drinking and said, unable to sleep, he had taken the tablets about 2am.

The latest revelation comes hard on the heels of his media conference at Punt Rd on Wednesday when the reformed drug addict said he found himself in a "bit of strife" after taking the sleeping tablets and was only lucky his girlfriend was on hand the following morning to get medical help. It was the third time this season he had been hospitalised.

"I guess it's probably a lesson for everybody. It's not just the medication you are taking, it's how much of it. It's been a big wake up call for me.

"I was in a bit of a bad way a couple of days ago but I have been able to tick the legs over today. I feel pretty fresh, full training tomorrow and I will do everything I can to get the match committee to pick me this week against against Freo. The boys are up and about.

"I don't remember a lot of it to be honest. I was asleep for the best part of it, so probably (it was) serious for the people around me. I was lucky my girlfriend was there."

It's understood Cousins' sleeping tablets were not the regular Stilnox or Temazepam, rather a prescribed sedative for his chronic sleeping problems.

"It's between me and my doctor. It's above board, it's not illegal or anything untoward," Cousins insisted.

"It's something that has been prescribed to me with a fair bit of thought process going into it. It's just probably an error of my judgement."

Cousins said he would no longer take the tablets after he was unable to be roused on Monday morning by his girlfriend, Maylea Tinecheff.

"I won't. Once bitten, twice shy. It's a serious thing and something I have got to continue to re-evaluate," he said.

Cousins arrived at Punt Rd with a cup of coffee in hand,  joking to reporters it was "only de-caff". But his troubles this weekend dealing with "uppers" - caffeine stimulants to boost his energy during games - and "downers", sleeping tablets, have cast a shadow over all AFL players.

"I don't think it's been abused. I just think for stuff like that it's important to consult your club doctor," Cousins said.

"It's certainly not an illegal substance. A cup of coffee virtually does the same thing. I haven't seen it abused and I think to abuse caffeine probably has an adverse effect on your performance."

Cousins also justified his decision to call the AFL doctor Peter Harcourt and insist he be drug tested.

"I think it was important with my history and speculation and innuendo that surrounds anything that happens to me, there is always going to be that speculation," he said.

"It (speculation) certainly wasn't of an innocent nature. I just thought it was an opportunity to clear my name from that point of view."

While he remains confident of playing out the season, Cousins now appears increasingly unlikely to be given a new contract for next year.

He hopes to play on but understands that wish may not be granted.

"It's more something I think the club is continually assessing," he said.

"I have got eight games of footy that I am looking forward to. I am hoping to play good footy, justify my existence. I will sit down with the coach and see what they have in store.

"I have had a great time at Richmond. If it comes to and end at the end of the year, I won't leave bitter and twisted.

"It's been an amazing club to be involved in. They have given me an opportunity to get my life back on track. So, if it ends now it will be disappointing but I will walk away a happy person."

Cousins is drug tested up to three times a week by the AFL but the man himself has spoken of his fears about remaining "clean" when he no longer has the support and direction of an AFL club around him.

After his off-field drug-fuelled antics were exposed while with the West Coast Eagles, Cousins was deregistered for the 2008 season for bringing the game into disrepute.

Cousins was hospitalised twice on the eve of this season with what the Tigers have termed "gastric" issues.