Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash flows from operating activities:
Net loss	$ (2,887)	$ (3,189)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	151	20
Stock-based compensation expense	185	136
Board fees paid with common stock	45	0
Change in fair value of common stock warrants	69	(1,170)
Non-cash expense of issuing shares to Aspire Capital	602	0
Change in fair value of contingent consideration	5	19
Change in operating assets and liabilities:
Accounts receivable	23	(31)
Inventory	(195)	(102)
Prepaid expenses and other assets	(15)	(49)
Accounts payable	(175)	627
Accrued compensation and other current liabilities	46	(317)
Other long-term liabilities	(37)	72
Net cash used in operating activities	(2,183)	(3,984)
Cash flows from investing activities:
Purchase of property and equipment	(4)	(19)
Net cash used in investing activities	(4)	(19)
Cash flows from financing activities:
Proceeds from issuance of common stock	10,000	0
Net cash provided by financing activities	10,000	5,000
Net increase in cash and cash equivalents	7,813	997
Cash and cash equivalents, beginning of period	2,726	5,495
Cash and cash equivalents, end of period	10,539	6,492
Supplemental disclosures of noncash investing and financing information
Conversion of preferred stock to common stock	0	1,665
Issuance of common stock in Essentialis acquisition	18,786	0
Costs of Essentialis acquistions included in accounts payable	572	0
Contingent consideration of Essentialis acquisition	1,090	0
Fixed asset purchases in accounts payable	0	0
Series A Convertible Preferred Stock [Member]
Cash flows from financing activities:
Proceeds from sale of Series A preferred convertible stock	0	5,071
Series A preferred convertible stock transaction costs paid	0	(71)
Series B Convertible Preferred Stock [Member]
Supplemental disclosures of noncash investing and financing information
Conversion of preferred stock to common stock	6	0
Series B Warrant Liability [Member] | Cash Less Exercise [Member]
Supplemental disclosures of noncash investing and financing information
De-recognition of Series B warrant liability (cashless exercise)	$ 0	$ 593