|
Thank you for entrusting in the compounding services at MD Custom Rx to help meet the unique medication needs of your patients. We are excited to share with you our monthly newsletter and look forward to continuing to be your medication problem solvers. Please don't ever hesitate to let us know how we can be of further assistance to you and your practice.
Sincerely,
John, Dan and Monica |
Metformin Transdermal for Diabetic Patients Unable to Tolerate Oral Metformin
Metformin is considered a first-line treatment in the management of insulin resistance and type 2 diabetes mellitus. Metformin can also decrease triglycerides levels and has also been associated with a modest weight loss. Adverse side effects are frequent in patients taking metformin; the most notable being gastrointestinal reactions in up to 20% of patients taking oral metformin, including anorexia, nausea, vomiting, abdominal discomfort and diarrhea. The effects are dose related and up to 5% of patients will discontinue oral metformin therapy due to the side effects. 77% of patients taking metformin will also develop a vitamin B 12 deficiency, which has been associated with peripheral neuropathy.
The bioavailability of oral metformin is only 50-60% under fasting conditions. Food delays the absorption. Gastrointestinal side effects frequently lead patients to not take metformin on an empty stomach, further reducing the bioavailability. Orally administered metformin is degraded in the GI tract.
Transdermal metformin has been studied as an alternative treatment in patients with insulin resistance who are unable to tolerate oral medications. One advantage of using transdermal metformin is that it bypasses the gastrointestinal system, and therefore does not produce the gastrointestinal side effects associated with oral metformin. Transdermal metformin is dosed at only 5-10% of the typical oral dose, and this significantly reduced actual dose has achieved effects that are clinically comparable to the typical oral dose. Reduced incidence of adverse effects has improved compliance and tolerability for patients who have difficulty swallowing oral agents.
In clinical use, transdermal delivery of metformin formulated with Pluronic Lecithin Organogel, it was observed that approximately 5-10% of the amount of the usual oral dose elicited a therapeutic response in terms of decreased blood-glucose levels. For example, if a patient was taking 1000 mg of metformin by mouth twice daily, an equivalent transdermal preparation would be 50 to 100 mg transdermally twice daily. This can be achieved by the patient applying as little as 0.5 ml (50mg) of metformin 10% transdermal gel applied to the skin twice daily. In other words, the amount of metformin as an active pharmaceutical ingredient administered transdermally is usually only 25-100 mg twice daily. Therefore, it is important that patients are carefully monitored during changes in medication.
|
Topical Nifedipine in the Treatment of Facial Wrinkles
Over the past two decades, there has been increasing demand for aesthetic procedures to reverse the effects of aging, particularly in the facial area. Topical nifedipine has been investigated recently for its anti-wrinkle efficacy.
A randomized study was conducted in 20 healthy female volunteers, aged between 45 and 60 years, with moderate to moderately severe facial wrinkles, to confirm the anti-wrinkle efficacy of a nifedipine 0.5% topical formulation. Ten volunteers applied a 0.5% nifedipine cream and 10 volunteers applied a good moisturizer twice daily for 90 days. The aesthetic improvement was evaluated by a blinded investigator using the Wrinkle Severity Rating Scale (WSRS). Anti-wrinkles effectiveness was also objectively assessed by measuring transepidermal water loss (TEWL), moisture levels of the stratum corneum, skin viscoelasticity and skin folding capacity by instrumental analysis.
Post-treatment WSRS score was significantly lower than the baseline WSRS score only in the nifedipine group. The mean WSRS score at T0 was 3.85 and at T3 was 1.84 in the nifedipine group, while the mean WSRS score at T0 was 3.78 and at T3 was 3.36 in the control group. Corneometry showed significant increases in measures of skin hydration and TEWL values decreased in all the patients of both groups, indicating a trend toward improved integrity of skin. Dermolab® recorded significant increases in measures of skin hydration in the nifedipine group and a lower increase in the control group. The colorimetric evaluation showed that use of the tested product resulted in significant overall lightening of the skin during use compared with baseline, while the moisturizer didn't produce any change of skin lightening parameters.
The study concluded that the tested topical preparation was effective in reducing facial wrinkles' depth and in increasing skin hydration and elasticity.
|
Nifedipine Topical Formulation for Treatment of Cutaneous Lesions
Nifedipine has been used topically for the treatment of cutaneous lesions caused by peripheral vascular disease and diabetic ulcers. Nifedipine 8% was formulated in three semi-solid formulations: Polaxamer 407 Lecithin Organogel (PLO), PLO plus Transcutol®, and an oil-in-water (o/w) emulsion. In vitro release and permeation tests were carried out using a synthetic (cellulose acetate) or natural membrane (pig ear skin). The penetration profiles of the three formulations in both the epidermis and dermis were statistically different. The incorporation of nifedipine in various bases (PLO, PLO plus Transcutol®, and o/w emulsion) changed the drug's thermodynamic activity. Use of a permeation enhancer increased the solubility of nifedipine in the formulation and promoted its penetration in both the epidermis and dermis.
Our compounding professionals can prepare customized medications for administration via the most appropriate route and in the best dose to reduce the incidence of side effects.
The type of base used for the preparation determines the extent of absorption, and whether the benefit is primarily systemic or local.
We welcome your questions and your medication problems, and the opportunity to work with patients and their physicians to optimize therapeutic benefits or reduce side effects.
|
|
|
|