**2.2 Heart disease and diabetes**

As noted above, patients with heart disease and diabetes are more likely to develop severe COVID-19. Thus, many of these patients will be given medications for COVID-19 on top of the current heart/diabetes medications they take. For example, patients continue to take ACE inhibitors or angiotensin II receptor blockers (ARBs) during COVID-19 infection [17]. Furthermore, these are the patients more likely to benefit from dietary ingredients that assist in preventing or treating COVID-19. Due to multiple treatments at once, the likelihood of drug–drug and drug-herb


#### **Table 1.**

*Metabolism and excretion of some common medications used in COVID-19, heart disease and diabetes.*

interaction in these patients is high. Drug treatments for heart disease include several types: anticoagulants, antiplatelets, ACE inhibitors, ARBs, beta blockers, calcium channel blockers, cholesterol lowering, diuretics, and vasodilators [19]. For diabetes main medication classes include sulfonylureas, meglitinides, metformin, and glitazones [20]. The metabolism of some commonly prescribed of these medications are listed in **Table 1**. As noted, the most common cytochrome P450 enzyme involved in the metabolism of these drugs are CYP3A4, followed by CYP2C9, 2D6, and 2C8 [21–25]. Approximately half of them are primarily excreted via the kidneys.
