Cutaneous Reactions to Transdermal Therapeutic Systems

The novel function of bexarotene for neurological diseases

Bexarotene, a retinoid X receptor (RXR) agonist, is approved by FDA to treat cutaneous T-cell lymphoma. However, it has also demonstrated promising therapeutic potential for neurological diseases such as stroke, traumatic brain injury, Parkinson's disease, and particularly Alzheimer's disease(AD). In AD, bexarotene inhibits the production and aggregation of amyloid β (Aβ), activates Liver X Receptor/RXR heterodimers to increase lipidated apolipoprotein E to remove Aβ, mitigates the negative impact of Aβ, regulates neuroinflammation, and ultimately improves cognitive function. For other neurological diseases, its mechanisms of action include inhibiting inflammatory responses, up-regulating microglial phagocytosis, and reducing misfolded protein aggregation, all of which aid in alleviating neurological damage. Here, we briefly discuss the characteristics, applications, and adverse effects of bexarotene, summarize its pharmacological mechanisms and therapeutic results in various neurological diseases, and elaborate on the problems encountered in preclinical research, with the aim of providing help for the further application of bexarotene in central nervous system diseases.

Patch Test Reactions Associated With Topical Medications: A Retrospective Analysis of the North American Contact Dermatitis Group Data (2001-2018)

BACKGROUND/OBJECTIVES

Topical medications may lead to allergic contact dermatitis. This study characterized positive patch test reactions associated with medications in patients evaluated by the North American Contact Dermatitis Group (NACDG).

METHODS

This study is a retrospective analysis of the NACDG data (2001-2018). Patients with at least 1 positive patch test reaction associated with a medication source were included. Allergens, reaction characteristics, clinical relevance, and source details were tabulated.

RESULTS

Of 43,722 patients, 6374 (14.6%) had positive allergic patch test reactions associated with 1 or more topical medication sources. Patients with versus without allergic reactions to medications were more likely to be older than 40 years (P < 0.0001) and/or have primary sites of dermatitis on the legs, anal/genital region, or trunk (P < 0.0001). There were 8787 reactions to NACDG allergens; the most common were neomycin (29.4%), bacitracin (29.1%), propylene glycol 100% (10.6%), tixocortol-17-pivalate (10.0%), lidocaine (7.9%), budesonide (4.9%), and dibucaine (4.4%). Propylene glycol 100% was the most common inactive ingredient (10.6%). Current relevance was present in 61.0%. A total of 6.5% of the individuals with medication allergy would have had 1 or more positive patch test reactions missed if only tested to the NACDG screening series.

CONCLUSIONS

Positive patch test reactions associated with topical medications were common (14.6%), and most were clinically relevant. Patients with topical medication allergy were twice as likely to have anal/genital involvement. Active ingredients, especially neomycin, bacitracin, and tixocortol-17-pivalate, were frequent culprits.

Cutaneous irritancy of an ibuprofen medicated plaster in healthy volunteers

OBJECTIVE

Ibuprofen is a commonly used non-steroidal anti-inflammatory drug administered to treat injuries, joint pain, and recurrent muscular skeletal pain. The aim of this study was to determine the cutaneous irritancy of a medicated ibuprofen plaster compared with a placebo plaster in healthy volunteers.

METHODS

Healthy volunteers (N = 31) were treated at the same time with one ibuprofen and one placebo plaster. The ibuprofen and placebo plaster were applied in a randomized fashion to sites on the left or right side of subjects' lower backs. At each scheduled visit, the plasters and applications sites were assessed for degree of adhesion and skin irritancy, respectively. The plasters were applied on study Days 1, 2, 3, 5, 8, 10, 12, 15, 17, and 19, with final plaster removal on Day 22.

RESULTS

The ibuprofen medicated plaster compared with placebo had a lower percentage of Grade 1 (23.3% vs. 46.7%, respectively), Grade 2 (10% vs. 20%), and ≥Grade 3 (3% vs. 16.1%) irritancy scores after 21 days of application. The mean irritation score across the study was 0.40 for the ibuprofen medicated plaster and 1.18 for the placebo plaster. The irritation score on Day 22 of the study was 0.53 for the ibuprofen medicated plaster and 1.50 for placebo. The placebo plaster was associated with a higher number of stopped applications due to Grade 3 or above skin reactions compared with the ibuprofen medicated plaster (5 vs. 1, respectively).

CONCLUSION

The ibuprofen medicated plaster was well tolerated and was associated with lower irritancy than the placebo plaster.

Adverse Drug Reactions of the Lower Extremities

Adverse drug reactions (ADRs) are a common cause of dermatologic consultation, involving 2 to 3 per 100 medical inpatients in the United States. Female patients are 1.3 to 1.5 times more likely to develop ADRs, except in children less than 3 years of age, among whom boys are more often affected. Certain drugs are more frequent causes, including aminopenicillins, trimethoprim-sulfamethoxazole, and nonsteroidal antiinflammatory drugs. Chemotherapeutic agents commonly cause adverse reactions to the skin and nails, with certain agents causing particular patterns of reactions. ADRs can involve any area of the skin; the appendages, including hair and nails; as well as mucosa.

Methylphenidate transdermal system: a multisite, open-label study of dermal reactions in pediatric patients diagnosed with ADHD

OBJECTIVE

To characterize dermal reactions and examine methylphenidate (MPH) sensitization in subjects receiving methylphenidate transdermal system (MTS).

METHOD

This multicenter, open-label, dose-optimization study utilized MTS doses of 10, 15, 20, and 30 mg in children aged 6 to 12 years, inclusive (N = 305), with a DSM-IV-TR primary diagnosis of attention-deficit/hyperactivity disorder. The study was conducted between January 8, 2007, and August 23, 2007. Subjects wore MTS on their hips for 9 hours per day, alternating sides daily for a total of 7 weeks. Assessments included the Experience of Discomfort scale, Transdermal System Adherence scale, and Dermal Response Scale (DRS; 0 = no irritation, 7 = strong reaction). On-study reevaluations were conducted to characterize DRS scores ≥ 4. Epicutaneous allergy patch testing was conducted for DRS scores ≥ 6, persistent DRS scores ≥ 4, DRS score increase following an assessment of ≥ 4, or DRS scores of 4 or 5 following elective discontinuation.

RESULTS

Approximately half of subjects experienced definite erythema at the patch site that generally dissipated within 24 hours. Four subjects experienced a DRS score of 4 (1%): erythema in 1 subject resolved on study treatment, 2 cases resolved poststudy and subjects tolerated oral MPH, and 1 subject discontinued treatment. The latter subject was referred for patch testing and was diagnosed with allergic contact sensitization to MPH.

CONCLUSIONS

Few severe dermal effects were seen with MTS treatment. Dermal reactions were characterized as contact dermatitis and dissipated rapidly. On patch testing, 1 subject (0.3%) manifested sensitization to MPH.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00434213.

The role of intranasal estradiol spray in the management of moderate to severe vasomotor symptoms in menopausal women

Hormone therapy (HT) is the most effective treatment at present available for climacteric symptoms. As harmful effects were highlighted in recent randomized clinical trials, the risk-benefit ratio does not favor the use of HT for prevention of cardiovascular diseases and bone fractures in postmenopausal women. Nevertheless, experimental and clinical trials suggest that adverse effects of HT basically depend on the estrogen and progestin formulation, dosage, route of administration, patient's age, associated diseases, and duration of treatment. All estrogen formulations and routes of administration have comparable beneficial effects on vasomotor and urogenital symptoms and on bone structure. But adverse effects may differ. Thus, cardiovascular and invasive breast cancer risks are higher with oral estrogen than with transdermal estradiol. However, transdermal estradiol is not free of inconveniences such as differences among individuals in absorption rates, loss of patches due to poor adhesion, and skin irritation. HT requires careful adjustment to each individual patient and continuous monitoring of clinical evolution. In the future, this adjustment and maybe the use of alternative routes such as intranasal could benefit from genetic screening to maximize in each individual the ratio between positive and adverse effects of HT.

Practical management of cutaneous reactions to the methylphenidate transdermal system: recommendations from a dermatology expert panel consensus meeting

BACKGROUND

Psychostimulants remain the most-used medications for attention-deficit/hyperactivity disorder (ADHD). The methylphenidate transdermal system (MTS) is the first stimulant patch dosage formulation to be approved by the US Food and Drug Administration for the treatment of the symptoms of ADHD in children aged 6 to 12 years. The MTS patch is approved to be applied once daily to the hip and worn for 9 hours. While cutaneous reactions may occur with any formulation of medication, they are more likely with transdermal administration.

OBJECTIVE

The purpose of this commentary was to describe the types of cutaneous reactions that have been reported with transdermal systems in general, review the cutaneous adverse events seen in clinical trials with the MTS specifically, and provide practical management suggestions for prevention and treatment of these potential cutaneous reactions.

METHODS

In September 2007, a group of child psychiatrists, pediatricians, developmental pediatricians, and pediatric neurologists who treat ADHD and have had experience in their practices with MTS convened to discuss cutaneous reactions in relation to its use. Information collected from this meeting and from the clinical trials database of the sponsor was reviewed by a panel of 3 dermatologic clinical experts in contact dermatitis and 1 pediatric dermatologist. The panel's recommendations form the basis for this report.

CONCLUSIONS

Mild to moderate erythema is a common cutaneous effect with MTS use, and is generally not a cause for discontinuation if seen in isolation. Irritant contact dermatitis is relatively common and can be reduced and treated by alternating patch application sites, moisturizing, gentle skin care, and application of topical corticosteroids at the previous patch sites if needed. Allergic contact dermatitis (ACD) and allergic contact urticaria are rare when MTS is worn as directed in the prescribing information. MTS should be discontinued if ACD is suspected.

[Transdermal therapeutic systems for drug administration]

Transdermal therapeutic systems, or transdermal patches, facilitate controlled release of active ingredients through the skin and into the systemic circulation. Drugs administered through such systems escape first pass metabolism and steady state is maintained similar to a continuous intravenous infusion for up to several days. Few pharmacologically active substances can currently be administered through transdermal patches and production is technically demanding. Research is ongoing to improve the systems and expand the indications. This article gives a brief overview over principles behind various transdermal patch types, as well as the advantages and disadvantages of transdermal therapeutic systems.

Transdermal hormone therapy in postmenopausal women: a review of metabolic effects and drug delivery technologies

Vasomotor symptoms (VMS) associated with menopause can cause significant discomfort and decrease the quality of life for women in the peri-menopausal and post-menopausal stages of life. Hormone therapy (HT) is the mainstay of treatment for menopausal symptoms and is currently the only therapy proven effective for VMS. Numerous HT options are available to treat VMS, including estrogen-only and estrogen-progestogen combination products to meet the needs of both hysterectomized and nonhysterectomized women. In addition to selecting an appropriate estrogen or estrogen-progestogen combination, consideration should be given to the route of administration to best suit the needs of the patient. Delivery systems for hormone therapy include oral tablets, transdermal patches, transdermal topical (nonpatch) products, and intravaginal preparations. Oral is currently the most commonly utilized route of administration in the United States. However, evidence suggests that oral delivery may lead to some undesirable physiologic effects caused by significant gut and hepatic metabolism. Transdermal drug delivery may mitigate some of these effects by avoiding gut and hepatic first-pass metabolism. Advantages of transdermal delivery include the ability to administer unmetabolized estradiol directly to the blood stream, administration of lower doses compared to oral products, and minimal stimulation of hepatic protein production. Several estradiol transdermal delivery technologies are available, including various types of patches, topical gels, and a transdermal spray.