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Olsalazine sodium

European Pharmacopoeia (EP) Reference Standard

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4,4′-Dihydroxyazobenzene-3,3′-dicarboxylic acid disodium salt, 5,5′-Azobis(salicylic acid, sodium salt), Mordant Yellow 5
Empirical Formula (Hill Notation):
CAS Number:
Molecular Weight:


pharmaceutical primary standard

API family





pharmaceutical (small molecule)



storage temp.




InChI key


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General description

This product is provided as delivered and specified by the issuing Pharmacopoeia. All information provided in support of this product, including SDS and any product information leaflets have been developed and issued under the Authority of the issuing Pharmacopoeia.For further information and support please go to the website of the issuing Pharmacopoeia.


Olsalazine sodium EP Reference standard, intended for use in laboratory tests only as specifically prescribed in the European Pharmacopoeia.


The product is delivered as supplied by the issuing Pharmacopoeia. For the current unit quantity, please visit the EDQM reference substance catalogue.

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Gerassimos J Mantzaris et al.
The American journal of gastroenterology, 99(6), 1122-1128 (2004-06-08)
The aim of this prospective study was to assess whether the coadministration of azathioprine (AZA) and olsalazine is superior to AZA monotherapy in maintaining remission of steroid-dependent ulcerative colitis (UC). Patients with steroid-dependent UC in remission were randomized to receive
Laurie M Edmond et al.
Inflammatory bowel diseases, 9(1), 10-17 (2003-03-27)
The toxic, bacterial metabolite sulfide is implicated in ulcerative colitis. Ulcerative colitis patients taking 5-aminosalicylic acid-containing drugs have lower fecal sulfide levels than those not taking these drugs. The effects of sulfasalazine, balsalazide, olsalazine, and 5-aminosalicylic acid on sulfide production
Florian Loher et al.
The Journal of pharmacology and experimental therapeutics, 305(2), 549-556 (2003-02-28)
Mesopram, a specific inhibitor of type-4 phosphodiesterase, decreases the synthesis of tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). In the present study, we investigated the effect of mesopram in dextran sulfate sodium (DSS)-induced murine colitis. In the preventive model, colitis
M V Singer et al.
Hepato-gastroenterology, 53(69), 317-321 (2006-06-27)
In the treatment of ulcerative colitis, 5-aminosalicylic acid is the standard therapy for both acute exacerbations of the disease and the maintenance of remission. Clinical studies have shown that olsalazine (Dipentum)--a prodrug converted to two molecules of 5-ASA by colonic
When less is not more but at least equivalent.
Stephen Holland
Inflammatory bowel diseases, 10(6), 890-891 (2005-01-01)

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