Lactose Hydrous
Excipient (pharmacologically inactive substance)
What is Lactose Hydrous?
Lactose (C12H22O11) is milk sugar. It is a disaccharide composed of one galactose and one glucose molecule. In the pharmaceutical industry, lactose is used to help form tablets because it has excellent compressibility properties. It is also used to form a diluent powder for dry-powder inhalations. Lactose may be listed as lactose hydrous, lactose anhydrous, lactose monohydrate, or lactose spray-dried.[1]
People who are lactose intolerant do not have the enzymes needed to digest lactose. Most medications do not contain enough lactose to cause lactose intolerance. But some patients with severe lactose intolerance may experience symptoms. Lactose can be found in birth control pills, and some OTC drugs to treat stomach acid or gas.[2] Patients who are specifically "allergic" to lactose (not just lactose intolerant) should not use tablets containing lactose, or ask their health care provider prior to use.
[1] Dave RH. Overview of pharmaceutical excipients used in tablets and capsules. Drug Topics (online). Advanstar. 10/24/2008 http://drugtopics.modernmedicine.com/drugtopics/Top+News/Overview-of-pharmaceutical-excipients-used-in-tabl/ArticleStandard/Article/detail/561047. Accessed 08/19/2011
[2] Anon. Lactose Intolerance. National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health. NIH Publication No. 09–2751,June 2009; http://digestive.niddk.nih.gov/ddiseases/pubs/lactoseintolerance/#products. Accessed 08/19/2011
Top Medications Containing Lactose Hydrous
- Alprazolam 1 mg (Actavis)
- Alprazolam 0.5 mg (Actavis)
- Amiloride Hydrochloride and Hydrochlorothiazide 5 mg / 50 mg (Mylan Pharmaceuticals Inc.)
- Chlorzoxazone 500 mg (Teva Pharmaceuticals USA)
- Cognex 40 mg (First Horizon Pharmaceutical Corporation)
- Cognex 30 MG (Sciele Pharma Inc.)
- Glimepiride 4 mg (Prasco Laboratories)
- Glimepiride 2 mg (Prasco Laboratories)
- Glimepiride 1 mg (Prasco Laboratories)
- Hydromorphone Hydrochloride 4 mg (Ethex Corporation)
- Hydromorphone Hydrochloride 2 mg (Ethex Corporation)
- Hydromorphone Hydrochloride 8 mg (Ethex Corporation)
- Loperamide Hydrochloride 2 mg (Mylan Pharmaceuticals Inc.)
- Parafon Forte DSC 500 mg (Janssen Pharmaceuticals)
- Piroxicam 20 mg (Mylan Pharmaceuticals Inc.)
- Piroxicam 10 mg (Mylan Pharmaceuticals Inc.)
- Sulfamethoxazole and Trimethoprim 400 mg / 80 mg (Teva Pharmaceuticals USA)
- Sulfamethoxazole and Trimethoprim DS 800 mg / 160 mg (Teva Pharmaceuticals USA)


