Table 2.

Active pharmaceutical ingredients reported as known or suspected precursors of N-nitrosamines.

Order	Compounds	Order	Compounds	Order	Compounds
1	Aminopyraminea	21	Chlortetracycline	41	Methylene Blueb
2	Alfentanil	22	Cilostazol	42	Mifepristone
3	Aminophenazone	23	Citalopram	43	Minocycline
4	Amitriptyline	24	Clarithromycin	44	Nizatidine
5	Azithromycin	25	Clomipramine	45	Oleandomycind
6	Benzalkonium Chloridea	26	Diethyltoluamide	46	Olmesartan
7	Candesartan	27	Diltiazem	47	Oxytetracycline
8	Carbinoxamine	28	Dimenhydrinate	48	Promazine
9	Cefamandole	29	Diphenhydramine	49	Propoxyphene
10	Cefazolin	30	Doxepin	50	Quinupristin
11	Cefmenoxime	31	Doxylamine	51	Ranitidine
12	Cefonicid	32	Erythromycin	52	Roxithromycin
13	Cefoperazone	33	Escitalopram	53	Spiramycin
14	Cefotetan	34	Imipramine	54	Sumatriptan
15	Cefotiam	35	Irbesartan	55	Tetracycline
16	Cefpiramide	36	Losartan	56	Tramadol
17	Chloramphenicola	37	Meropenem	57	Trimipramine
18	Chlorpheniramine	38	Metformin	58	Venlafaxine
19	Chlorpromazine	39	Methapyrileneb
20	Chlorprothixene	40	Methyl Orangec

Drugbank dataset covers drug products approved by the FDA, Health Canada and EMA; including some withdrawn drug products as well.

^aAminopyramine, benzalkonium chloride, and chloramphenicol were not detected.

^bMethapyrilene was withdrawn from the market in 1979.

^cMethyl orange and methylene blue are not collected in Drugbank as approved drugs.

^dOleandomycin, a synthesized macrolide antibiotic, is an approved vet medicine.