Note 7 - Warrants (Details Textual) - USD ($)				3 Months Ended		12 Months Ended
	Feb. 22, 2018	Feb. 12, 2018	May 24, 2017	Mar. 31, 2018	Mar. 31, 2017	Jul. 17, 2017	Feb. 21, 2018	Dec. 11, 2017	Dec. 10, 2017	Dec. 30, 2016	Jul. 08, 2016
Interest Expense, Total				$ 832,408	$ 953,636
Class of Warrant or Right, Issued During Period				2,611,513	219,298
Deemed Dividends				$ 297,439
Lincoln Park Capital Fund, LLC [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	1,198,784
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 0.25						$ 0.394
Shares Issued, Price Per Share	$ 0.25
Deemed Dividends	$ 297,439
Warrants Issued Concurrently to the Spring 2018 Unit Offering [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights				333,333
Class of Warrant or Right, Exercise Price of Warrants or Rights				$ 0.48
Discount On Convertible Note Payable				$ 49,306
Class of Warrant or Right, Exercise Period Condition, Number of Trading Days Common Stock Closes at or above 2 Times the Exercise Price				30 days
Warrant Subject to Call provision, Threshold Consecutive Trading Days				10 days
Warrants Issued Concurrently with Line of Credit [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights				390,000
Class of Warrant or Right, Exercise Price of Warrants or Rights				$ 0.35
Discount On Convertible Note Payable				$ 85,002
Class of Warrant or Right, Exercise Period Condition, Number of Trading Days Common Stock Closes at or above 2 Times the Exercise Price				30 days
Warrant Subject to Call provision, Threshold Consecutive Trading Days				10 days
Warrants Issued Concurrently with Note Payable [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights				150,000
Class of Warrant or Right, Exercise Price of Warrants or Rights				$ 0.35
Discount On Convertible Note Payable				$ 4,875
Warrants Vested Monthly Contingent That Outstanding Note Payable is Present				6,250
Minimum Number of Warrants Vested For the Life of the Outstanding Note Payable				25,000
Minimum Number of Warrants Vested For the Life of the Outstanding Note Payable, Fair Value Amount				$ 6,500
Interest Expense, Total				$ 1,625
Warrants Issued Concurrently to the Summer 2017 Unit Offering [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 0.30
Discount On Convertible Note Payable		$ 103,322
Class of Warrant or Right, Exercise Period Condition, Number of Trading Days Common Stock Closes at or above 2 Times the Exercise Price			10 days
Class of Warrant or Right, Issued During Period		416,478		266,667
Proceeds from Convertible Debt				$ 80,000
Warrants Issued Concurrently With One Year Convertible Note [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights								2,081,216	1,200,000
Class of Warrant or Right, Exercise Price of Warrants or Rights						$ 0.65		$ 0.394		$ 0.70	$ 0.65
Class of Warrant or Right, Issued During Period						400,000
Proceeds from Convertible Debt						$ 250,000
Warrant Term						5 years