Two key steps that affect oral bioavailability of drugs are dissolution and gastrointestinal permeation. These two parameters are dictated by the intrinsic physicochemical properties of the drug, i.e., its aqueous solubility and lipophilicity (Jane et al. 2006). The aqueous solubility of the drug in question is a crucial factor because only drug in solution is destined for possible absorption. Dissolution of drug is largely determined by the aqueous solubility of drug, since a drug must be in solution to exert its beneficial effect (Patel et al. 2012). Good drug candidates should have high solubility and high lipophilicity. Unfortunately, lipophilicity also translates into high hydrophobicity and poor aqueous solubility (Rahman et al. 2011).
Nanotechnology world opens the field of delivering many of therapeutic agents in such a cell-specific manner with a maximum intrinsic activity of drugs. Therefore, to increase drug’s efficacy while decreasing their toxic side effects, it has been projected to encapsulate the drug in a nanocarrier (Fathi et al. 2012). Delivery thereby limiting off-target access, improving the bioavailability of poorly soluble drugs and enhancing intracellular delivery (Maravajhala et al. 2012).
Cardiovascular diseases include arterial diseases affecting the blood supply to the heart or to the brain, or to the peripheral regions of the body (Frayn 2005). Thiazide Diuretics, angiotensin converting enzyme inhibitors (ACE inhibitors), AT1 antagonists, β-blockers and calcium antagonists are drugs of first choice aim to prevent organ damage and reduce mortality rate (Bieger et al. 2005). Since it is a chronic disease, it necessitates long term treatment, but most of antihypertensive drugs available today showed extensive first pass metabolism, variable bioavailability and more frequent times of administration make them an ideal candidate for solid self-nanoemulsifying drug delivery (SSNEDDS) (Muhamad et al. 2014).