Condensed Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows from operating activities
Net loss	$ (9,354)	$ (7,504)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	79	367
Amortization of debt issuance costs and debt discount	42	44
Stock-based compensation	88	721
Noncash interest expense and other charges	858	753
Change in right of use asset	48	68
Provision for excess and obsolete inventories	86	22
Other non-cash charges	1	10
Gain on extinguishment of debt	0	(2,353)
Changes in operating assets and liabilities:
Accounts receivable	111	(314)
Inventories	(1,134)	(241)
Prepaid expenses and other current assets	(799)	(762)
Other assets	15	(44)
Accounts payable	(668)	343
Accrued compensation	(116)	(36)
Accrued expenses and other current liabilities	26	95
Other long-term liabilities	170	287
Net cash used in operating activities	(10,547)	(8,544)
Cash flows from investing activities
Purchase of property and equipment	(31)	(18)
Net cash used in investing activities	(31)	(18)
Cash flows from financing activities
Net cash provided by financing activities	7,120	13,077
Net change in cash and cash equivalents	(3,458)	4,515
Cash and cash equivalents, beginning of period	19,497	22,185
Cash and cash equivalents, end of period	16,039	26,700
Noncash investing and financing activities:
Accretion of Series A preferred stock dividends	2,254	2,088
Reclassification of right of use asset to prepaid rent	(48)	(68)
Transfers between inventory and property and equipment	471	(23)
Common Stock [Member]
Cash flows from financing activities
Proceeds from the issuance of convertible preferred stock, net of commissions and issuance costs	6,721	0
Preferred Stock [Member]
Cash flows from financing activities
Proceeds from the issuance of convertible preferred stock, net of commissions and issuance costs	$ 399	$ 13,077