Note 4 - Acquisition of Grace - Consideration (Details) - Grace Therapeutics Inc Member	Aug. 27, 2021 USD ($) $ / shares shares
Restructuring Cost and Reserve [Line Items]
Total common shares issued (in shares) \| shares	18,241,233
Acasti share price (closing share price on August 27, 2021) \| $ / shares	$ 3.3344
Fair value of common shares issued \| $	$ 60,824

Number of shares of equity interests issued or issuable to acquire entity.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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