Clindamycin Phosphate

Similar in structure to the antibiotic lincomycin from which it is derived, clindamycin. Clindamycin has previously been regarded as a potent anti-anaerobic antibiotic, but recent research has revealed that it also works well when combined with pyrimethamine to treat toxoplasmic encephalopathy in AIDS patients. 1. Clindamycin was FDA-approved in 1970 and is marketed as a phosphate salt for parenteral, topical, or vaginal administration in addition to its hydrochloride salt for oral management. In November 2004, the FDA approved ClindesseTM, a single-dose vaginal cream for bacterial vaginosis. In December 2004, the FDA approved EvoclinTM, an aerosol topical foam containing 1% clindamycin, for the management of acne vulgaris.

Niacinamide

A B-complex vitamin, niacin is also known as nicotinic acid or 3-pyridinecarboxylic acid. Animal proteins, beans, green vegetables, liver, mushrooms, peanuts, whole wheat, and unpolished rice are excellent dietary sources of niacin. Cereal grains contain niacin as well, although it is primarily attached to plant proteins and is therefore poorly absorbed after consumption. Niacin is one of the ingredients added to refined wheat to enrich it, and enriched grains account for the majority of the preformed niacin we consume each day. The manufacture of niacin from the amino acid tryptophan, however, also satisfies the body’s need for niacin. Niacin, for instance, is absent from milk and eggs but is abundant in tryptophan, which is the precursor of niacin. After protein synthesis, each excess 60 mg of tryptophan is converted to roughly 1 mg of niacin. Roughly half of a man’s niacin requirement is met by the synthesis of the vitamin from tryptophan in proteins. Due to the dependency of coenzymes in the niacin manufacturing route, iron shortage, poor pyridoxine, or riboflavin status will limit the conversion of tryptophan to niacin and may contribute to deficit. Pellagra is a clinical symptom complex that primarily affects the GI tract, skin, and CNS, producing symptoms of diarrhea, dermatitis, and dementia, respectively. It is a late and significant consequence of niacin insufficiency. Niacin and protein deficiencies, isoniazid medication, or specific conditions that cause poor tryptophan usage can all contribute to pellagra. Due to the enrichment of refined flours, pellagra is now uncommon in industrialized nations. Pellagra was the only vitamin deficiency disease to ever reach epidemic proportions in the US.

For both niacin and niacinamide, there are numerous synonyms. Nicotine might be converted into synthetic niacin through oxidation, leading to the development of the name “nicotinic acid.” The terms “nicotinamide” and “niacinamide” were also created by scientists to describe the amide form of nicotinic acid. Since the 1940s, foods have been labeled with the generic name “niacin” to prevent conflating the vitamin with the nicotine alkaloid found in tobacco. As a result, both chemical forms of niacin—which are comparable as vitamins on a weight basis—have been referred to as “niacin.” Nicotinamide and nicotinic acid are both produced for use in dietary supplements. It is crucial to distinguish between the two forms in pharmaceutical products because nicotinic acid and nicotinamide differ in their pharmacologic qualities from their function as vitamins.

Niacinamide, also known as nicotinamide, is ineffective as an antilipemic in clinical medicine; nevertheless, nicotinic acid is. The incidence of subsequent myocardial infarction (MI) and overall mortality in MI patients were both reduced by nicotinic acid, the first hypolipidemic drug to demonstrate these effects. However, no additional advantage of extended-release niacin combined with lovastatin or simvastatin over and above that shown for extended-release niacin, simvastatin, or lovastatin monotherapy on cardiovascular morbidity and mortality has been established. Additionally, the AIM-HIGH trial showed that simvastatin alone does not reduce the risk of cardiovascular events any more than simvastatin combined with extended-release niacin (1500–2000 mg/day PO). 2 These findings are in line with the larger HPS2-THRIVE trial, which found that adding extended-release niacin to efficient statin-based therapy did not lead to a higher decline in the risk of cardiovascular events. Additionally, there was a higher likelihood of major adverse effects, such as an increase in the frequency of diabetes diagnoses and control issues, serious gastrointestinal, musculoskeletal, dermatological, infectious, and bleeding problems. Additionally, the rate of deaths from any cause increased by a statistically insignificant 9 percent in the niacin group. 3 The ARBITER 6-HALTS experiment proved that the addition of extended-release niacin 2000 mg/day to statins is superior to the combination of ezetimibe plus a statin in that it causes a substantial regression in atherosclerosis as evaluated by carotid intima-media thickness. 4 In an MRI investigation, the addition of 2000 mg/day of extended-release niacin to statin medication significantly decreased the carotid wall area when compared to the control group. 5 However, the NIA Plaque study, which was presented at the 2009 Scientific Sessions of the American Heart Association (AHA), did not discover a substantial slowing of atherosclerosis progression linked to the addition of niacin to statin medication as compared to statin monotherapy. Additionally, nicotinic acid has been tried to treat tinnitus, but there are few reliable results. When compared to immediate-release versions, some sustained-release nicotinic acid formulations had a reduced incidence of flushing but a higher incidence of hepatotoxicity. 6 There are some dose forms that are offered over-the-counter. Niacin was formally approved by the FDA in 1938.

Tretinoin

All-trans-retinoic acid (ATRA), commonly known as tretinoin, is a naturally occurring vitamin A derivative. Retinoids are key regulators of cell division, proliferation, and differentiation as vitamin A (retinol) derivatives; however, unlike vitamin A, retinoids are not transformed into rhodopsin, which is required for night vision. Topical tretinoin is recommended for the treatment of photodamaged skin and mild to moderate acne (grades I–III). In order to treat the symptoms of keratinization disorders including ichthyosis and keratosis follicularis, topical tretinoin has also been employed. Tretinoin is a novel class of cancer-fighting medications known as differentiation agents. In addition to being used to treat Kaposi’s sarcoma, oral tretinoin is being investigated in phase III for the treatment of acute promyelocytic leukemia (APL). Tretinoin offers a less harmful way to achieve complete remission in the treatment of APL compared to traditional chemotherapy, however about 25% of patients who use tretinoin for the management of APL develop acute promyelocytic leukemia differentiation syndrome. 7