Introduction Diabetes mellitus disease is referred as a chronic pancreatic disease which affect the production of hormone insulin

Diabetes mellitus disease is referred as a chronic pancreatic disease which affect the production of hormone insulin. it affects patient ability to use food energy (Cleveland,2018). DM is classified into 2 types, which are DM type 1 and DM type 2. DM type1 result from autoimmune-mediated destruction of pancreatic B-cell, resulting in absolute deficiency of insulin. The incidence of the disease occurs more in young patients.
Diabetes mellitus type 2 (DM) is a complex metabolic disorder caused by a combination of a lack of insulin production or insulin resistance. Patients usually without symptoms, some symptoms include polyuria, lethargy and nocturia (therabook). DM is a critical cause of mortality and morbidity in the developed world especially complications of vascular disease like coronary vessels thrombosis. (Tang, Martin and Hwa,2012)
Several oral pharmacological agents have been approved for the management DM type 2. They are antidiabetic drugs used in monotherapy or combination therapy. (sang et al.,2014).
The first line pharmacotherapy that included in n ational and international guidelines is Metformin hydrochloride which belonging to the biguanide class. Metformin it’s insulin sensitizer that improve insulin sensitivity by reducing glucose absorption in the intestine inhibition, hepatic gluconeogenesis and lowering glucose production from the liver (M. A. Islam et al., 2014 should be older reference) Metformin used as monotherapy or combination with different mechanism of action drugs.
Monotherapy with metformin giving as initial therapy to lifestyle modification but frequently monotherapy be unsuccessful in maintain enough glycemic control above the long term, therefor, combination therapy in general required to obtain and maintain good glucose level (H.Y. Cho et al., 2009).
It is expected to progressively increas in diabetes mellitus patients to 366 million by the year 2030, due to the increasing cost of anti-diabetic medications, a heavy economic burden will be imposed on health care authorities. regarding that, there is a need to consider the less costly generic materials that are equivalent to their concerned brand products therapeutically and pharmaceutically (Saker et al,2016).
Generic drugs have an important role in lowering the cost of treatment in many countries. however, using of generics is continues to be controversial between healthcare professionals, pharmaceutical industry members and patients .in fact many generics can cause bioavailability problems, the therapeutic equivalence remain a great concern in the last ten years (Yun Sun et al.,2016) bioequivalence is a term used in pharmacokinetics to describe the similarity or absence of any essential characteristic difference in the bioavailability of the active ingredient between tow pharmaceutical product(…). generics are manufactured by a company differ from a company that produced the original drug that calls the brand. The FDA has regulation for approval the generic drugs, they have to pass guided list of examination and tests for example, the have to be bioequivalent to the brand, contain the same active ingredients and strength also the physiochemical characteristics, they don’t need to be the same inactive constituents (Nandyala,2018), regarding of that , drug regulatory agencies and World Health Organization regulatory agencies support the use of generic medicines because they reduce the coast of prescription drugs significantly (Yun Sun et al ,2016)
•To Evaluate the quality and bioequivalence of some randomly chosen Anti-Diabetic drug in Saudi Market
•To examine physician attitude toward brand and generics medications
•To assess if the patient can safely switch from one brand to another
Literature review
Physicians attitude regarding generics and brand prescription.
A study was conducted in Eastern region of Saudi Arabia 2017 to evaluate the levels of generic prescribing instead of brand drugs among type 2 diabetic and hypertensive. The study showed only 26.0% generic drugs were prescribed in 13 hospitals. It was also notice government hospitals prescribed 33.3% generics, private hospitals had 28.6% for same the patients category. In the community pharmacies prescribed 11.8% for hypertensive and 23.5% for diabetics patients. Overall the study finds low level of generic medications prescription. (J young pharma 2017).
Another study also conducted in Saudi Arabia in 2015 to investigate physicians attitude and perception of generics medications. The study carried out on random sample of 231 physicians in two different hospital the first one government the other one is private. The study show low prescription rate is notably more in government hospitals between senior-level physicians.(salhia,2015)
Equivalence of brand and generics:
A study carried out in India 2018 to investigate the quality and Price of Ranitidine and Metformin HCl Branded and Generic medications. The test includes Weight variation, Thickness, Friability, Hardness, Disintegration, dissolution and Assay. The study shows better results for branded medications comparing to generics in the tests, but values of generics were found to be within the limits(Nandyala,2018).
Another In vivo study in 17 healthy volunteers was conducted in Nigeria 2017 to evaluate bioequivalence of generic metformin tablets. The result shows Nine generic medications met the qualification assessment, the bioavailability of generics drugs was not lower than the brand. (Adegbola,2017).
Another study conducted in Saudi Arabia to assess and compare among six different Metformin hydrochloride brands which are available commercially in the Market of Saudi Arabia. Namely ( Dialon, Metaphage, Glucare, Formit, Metfor and the innovator Glucophage) All sex brands evaluated shows equivalence chemically and bio-pharmaceutically, it could be substituted with the brand product except Glucare. The patient can safely change from one brand to another(alafifi, 2012).
A study conducted in Jordan 2002 to evaluate bioequivalence of Dialon comparing to the brand product Glucophage. The study was carried out 24 fasting volunteer, healthy male. The statistical data shows Dialone is bioequivalent to the innovator Glucophage(badar,2002).
Patients perception of generic medication
A study was conducted in USA 2009 by using national survey of insurance patients to assess the perception regarding generic drugs. Overall the majority of patients have positive perception and agreed that generics are better value and lower price than branded drugs and just as safe. The minority of patient have concerns about the side effect and safety of generics and preferred brand-name drugs ( Shrank,2009).
Another study was conducted in 2008 to evaluate beliefs of elderly patient about generic medications. The study found many of low earning had suspicion with generics drugs, particularly elderly with low health education and African-Americans, also whose physicians have poor skills of communication. (Iosifescu
Materials and Methods