Initial prescription amounts are 500 mg/day, increased over time until a therapeutic effect is achieved. Immediate-release doses can be as high as 3,000 mg/day; sustained-release as high as 2,000 mg/day. Despite the proven lipid changes, niacin has not been found useful for decreasing the risk of cardiovascular disease in those already on a statin. A 2010 review had concluded that niacin was effective as a mono-therapy, but a 2017 review incorporating twice as many trials concluded that prescription niacin, while affecting lipid levels, did not reduce all-cause mortality, cardiovascular mortality, myocardial infarctions, nor fatal or non-fatal strokes. Prescription niacin was shown to cause hepatotoxicity and increase risk of type 2 diabetes. Niacin prescriptions in the U.S. had peaked in 2009, at 9.4 million, declining to 1.3 million by 2017.Niacin has the formula C6H5NO2 and belongs to the group of the pyridinecarboxylic acids. As the precursor for nicotinamide adenine dinucleotide and nicotinamide adenine dinucleotide phosphate, niacin is involved in DNA repair. Definition
Niacin is both a vitamin, i.e., an essential nutrient, marketed as a dietary supplement, and in the US, a prescription medicine. As a vitamin, it is precursor of the coenzymes nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP). These compounds are coenzymes for many dehydrogenases, participating in many hydrogen transfer processes. NAD is important in catabolism of fat, carbohydrate, protein, and alcohol, as well as cell signaling and DNA repair, and NADP mostly in anabolism reactions such as fatty acid and cholesterol synthesis.
Overdose
Overdose of ciprofloxacin may result in reversible renal toxicity. Treatment of overdose includes emptying of the stomach by induced vomiting or gastric lavage, as well as administration of antacids containing magnesium, aluminium, or calcium to reduce drug absorption. Renal function and urinary pH should be monitored. Important support includes adequate hydration and urine acidification if necessary to prevent crystalluria. Hemodialysis or peritoneal dialysis can only remove less than 10% of ciprofloxacin. Ciprofloxacin may be quantified in plasma or serum to monitor for drug accumulation in patients with hepatic dysfunction or to confirm a diagnosis of poisoning in acute overdose victims. Interactions
Ciprofloxacin interacts with certain foods and several other drugs leading to undesirable increases or decreases in the serum levels or distribution of one or both drugs. Ciprofloxacin should not be taken with antacids containing magnesium or aluminum, highly buffered drugs (sevelamer, lanthanum carbonate, sucralfate, didanosine), or with supplements containing calcium, iron, or zinc. It should be taken two hours before or six hours after these products. Magnesium or aluminum antacids turn ciprofloxacin into insoluble salts that are not readily absorbed by the intestinal tract, reducing peak serum concentrations by 90% or more, leading to therapeutic failure. Additionally, it should not be taken with dairy products or calcium-fortified juices alone, as peak serum concentration and the area under the serum concentration-time curve can be reduced up to 40%.