There are also time released versions available; that's what I've used
with great results for peripheral neuropathies.

Susan

There is more than one angle to look at the effects of alpha lipoic
acid.  There is the positive aspect that many diabetics have been
relieved of painful neuropathy using ALA therapy. On the other hand,
there is significant hyperglucagonemia in type 2 diabetics whereas the
pancreatic alpha cells secrete excessive glucagon which in turn results
in hyperglycemia.  Metformin partly offsets the excessive glucagon's
impact on the liver. Beta-cell mass, in which T2 are ~ 60% deficient at
diagnoses, relates to pulsatile insulin secretion.  Pulsatile insulin
secretion also results in inhibiting glucagon secretion.

The following study relating insulin secretion and glucagon secretion
was done in minipigs in which a significant level beta-cell were destroyed.

"Type 2 diabetes is characterized by an ~60% loss of ß-cell mass, a
marked defect in postprandial insulin secretion, and a failure to
suppress postprandial glucagon concentrations. It is possible that
postprandial hyperglucagonemia in type 2 diabetes is due to impaired
postprandial insulin secretion.  ... We conclude that postprandial
hyperglucagonemia in type 2 diabetes is likely due to loss of intraislet
postprandial suppression of glucagon secretion by insulin." Source:
Postprandial Suppression of Glucagon Secretion Depends on Intact
Pulsatile Insulin Secretion -
http://diabetes.diabetesjournals.org/cgi/content/abstract/55/4/1051

Autopsies pancreases of normal, T2 DMs, and impaired fasting glucose
patients were studied.
Relationship Between ß-Cell Mass and Fasting Blood Glucose Concentration
in Humans -
http://care.diabetesjournals.org/cgi/content/full/29/3/717

The following study was in healthy lean subjects.
"The current data indicate that ~80% of endogenous insulin secretion is
extracted during the first liver passage and that insulin clearance is
pulsatile, wherein the rate of prehepatic insulin secretion primarily
dictates time-varying clearance of endogenously secreted insulin.
Moreover, the pattern of insulin delivery by the pancreas (pulse mass
and therefore pulse amplitude) is the predominant determinant of
momentary hepatic insulin clearance. By implication, regulation of
insulin secretory-burst mass directly dictates the insulin concentration
wavefront presented to hepatocytes and indirectly dictates (by
modulating hepatic insulin clearance) insulin delivery to extrahepatic
insulin-sensitive tissues.

A major insight from the accompanying analysis is that the liver
responds minute-by-minute to changes in insulin concentration by
adaptively changing insulin clearance. This minute-to-minute adaptation
has important implications in delivery of insulin to the systemic
circulation. In health, insulin is secreted in distinct secretory bursts
every ~4 min (10). The minute-to-minute adaptive changes in insulin
clearance by the liver reported here in vivo reflect greater extraction
of the insulin within than between insulin secretory bursts. The fact
that absolute insulin clearance increases with insulin concentration
(6,31) agrees with the present observations that the liver clears larger
insulin secretory bursts to a greater extent than smaller insulin
pulses, given that at least 70% of insulin secretion is pulsatile. In
addition, analyses based on direct portal-vein catheterization
established an ~100-fold higher amplitude of insulin concentration
oscillations in the portal vein than in the peripheral circulation in
humans (18)."
Pulsatile Insulin Secretion Dictates Systemic Insulin Delivery by
Regulating Hepatic Insulin Extraction In Humans -
http://diabetes.diabetesjournals.org/cgi/content/full/54/6/1649

The effect of 3-month ingestion of Ginkgo biloba extract (EGb 761) on
pancreatic beta-cell function in response to glucose loading in
individuals with non-insulin-dependent diabetes mellitus -
http://jcp.sagepub.com/cgi/reprint/41/6/600
This article was cited in http://www.ajcn.org/cgi/content/full/81/1/243S
as Reference #10, author - Kudolo.  Earlier the full article was
available without going through the back door. ;) After reaching the
Kudolo abstract, click full pdf article .

I discontinued using Ginkgo biloba after reading the article about 3
years ago.  Sulphonylureas also stimulate insulin secretion.  This is
part of the problem with taking supplements.

Frank