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insulin glargine subcutaneous


This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

Medical warning:

Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

When these two medicines are taken together, the effect of insulin may be increased.

What might happen:

Your blood sugar may decrease, causing sudden onset of a cold sweat, dizziness, fatigue, shakiness, rapid heartbeat, nausea, weakness, headache, confusion, sweating, and hunger. If untreated, symptoms can progress to slurred speech and behaviors that resemble drunkenness.

What you should do about this interaction:

If you experience any of these signs of decreased blood sugar, contact your doctor. It may be necessary to check your blood sugar levels more often when starting or stopping treatment with these weight reduction medicines. You may also need to eat a quick source of sugar, such as table sugar or fruit juice.Your healthcare professionals (e.g. doctor or pharmacist) may already be aware of this drug interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine without checking with them first.


1.Turtle JR, Burgess JA. Hypoglycemic action of fenfluramine in diabetes mellitus. Diabetes 1973 Nov;22(11):858-67.
2.Harrison LC, King-Roach A, Martin FI, Melick RA. The effect of fenfluramine on insulin binding and on basal and insulin- stimulated oxidation of 1-14C-glucose by human adipose tissue. Postgrad Med J 1975;51 Suppl 1:110-4.
3.Salmela PI, Sotaniemi EA, Viikari J, Solakivi-Jaakkola T, Jarvensivu P. Fenfluramine therapy in non-insulin-dependent diabetic patients: effects on body weight, glucose homeostasis, serum lipoproteins, and antipyrine metabolism. Diabetes Care 1981 Sep-Oct;4(5):535-40.
4.Barseghian G, Lev-Ran A, Hwang D, Josefsberg Z, Tomkinson C. Fenfluramine inhibits insulin secretion and potentiates glucagon release by the perfused rat pancreas. Eur J Pharmacol 1983 Dec 9;96(1-2):53-9.
5.Pestell RG, Crock PA, Ward GM, Alford FP, Best JD. Fenfluramine increases insulin action in patients with NIDDM. Diabetes Care 1989 Apr;12(4):252-8.
6.Storlien LH, Thorburn AW, Smythe GA, Jenkins AB, Chisholm DJ, Kraegen EW. Effect of d-fenfluramine on basal glucose turnover and fat-feeding- induced insulin resistance in rats. Diabetes 1989 Apr;38(4):499-503.

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