Transdermal clonidine: therapeutic considerations

Engineering nanosystems for transdermal delivery of antihypertensive drugs

To control hypertension, long-term continuous antihypertensive therapeutics are required and five classes of antihypertensive drugs are frequently involved, including diuretics, β-blockers, calcium channel blockers, angiotensin II receptor blockers, and angiotensin-converting enzyme inhibitors. Although with demonstrated clinical utility, there is still room for the improvement of many antihypertensive drugs in oral tablet or capsule dosage form, in terms of reducing systemic side effects and first-pass hepatic drug uptake. Meanwhile, nanocarrier-mediated transdermal drug delivery systems have emerged as a powerful tool for various disease treatments. With benefits such as promoting patient compliance for long-time administration, enhancing skin permeability, and reducing systemic side effects, these systems are reasonably investigated and developed for the transdermal delivery of multiple antihypertensive drugs. This review aims to summarize the literature relating to nanosystem-based transdermal antihypertensive drug delivery and update recent advances in this field, as well as briefly discuss the challenges and prospects of engineering transdermal delivery nanosystems for hypertension treatment.

Novel Use of Clonidine Patch to Treat Tizanidine Withdrawal

Tizanidine is commonly prescribed for muscle spasticity and pain. Yet, withdrawal is rarely reported. Tizanidine stimulates presynaptic α-2 adrenergic and imidazoline receptors decreasing norepinephrine release. Abrupt cessation can cause withdrawal. Current treatment strategies include tapering oral tizanidine or substituting oral clonidine. A 52-year-old male with a history of hypertension, diabetes, coronary artery disease, and chronic back pain presented with altered mental status, agitation, hypertensive emergency (blood pressure: 250/145 mmHg), and tachycardia. The patient had been prescribed tizanidine for chronic back pain for two years and had recently run out with suspicion of misuse. Tizanidine withdrawal was diagnosed, and he improved with 0.1 mg oral clonidine three times daily weaned over five days while hospitalized. One month later the patient was admitted for persistent hypertension, tachycardia, diaphoresis, and anxiety. Alpha-2 agonist withdrawal was again diagnosed. Utilizing a clonidine patch taper may offer a reasonable approach in patients with tizanidine withdrawal.

Drugs for the treatment of postmenopausal symptoms: Hormonal and non-hormonal therapy

Postmenopausal symptoms are systemic symptoms associated with estrogen deficiency after menopause. At present, treatments for postmenopausal symptoms include hormonal therapy (HT) and non-HT. However, the optimal regimen for balancing the benefits and risks remains unclear. This article reviewed the characteristics, regimens, and side effects of drugs used in hormonal and non-HT. However, HT is still the most effective treatment with safety in early initiation since menopause onset. Nevertheless, it is essential to evaluate the risks of related chronic diseases and customize individualized treatments. Possible estetrol preparations and more types of Tissue Selective Estrogen Complex formulations are potential directions of drug development in the future of HT. Regarding non-HT, fezolinetant, currently in phase III clinical trials, is poised to become a first-in-class therapy for vasomotor symptoms. Ospemifene, dehydroepiandrosterone (DHEA), and vaginal lasers can also be used for moderate-to-severe genitourinary syndrome of menopause. Recent data suggest a superior efficacy and safety of vaginal lasers, but more validated evidence of long-term tolerability is needed to respond to the United States Food and Drug Administration warning. Herbal medication commonly used in Asia is effective in alleviating menopausal symptoms; however, its adverse effects still require more detailed reports and standardized observation methods. This review contributes to a better understanding of drugs for the treatment of postmenopausal symptoms and provides useful information for clinical drug selection.

Managing Common Estrogen Deprivation Side Effects in HR+ Breast Cancer: an Evidence-Based Review

PURPOSE OF REVIEW

The article reviews the consequences of estrogen deprivation during endocrine therapy for breast cancer and provides an update on alternative therapies for the management of symptoms.

RECENT FINDINGS

Endocrine therapy has progressed substantially in recent years, and its use is recommended for all breast cancer patients expressing hormone receptors. The main adverse events of this treatment can be controlled with medications and nonpharmacological measures. Antidepressants are effective in controlling vasomotor symptoms. Vaginal discomfort can be treated with local lubricants and pelvic floor physiotherapy, which may help in sexual dysfunction. Pathophysiological mechanisms of musculoskeletal symptoms during aromatase inhibitors treatment are not well understood, but some studies evaluating treatment with duloxetine, yoga, and acupuncture have shown some benefits. For prevention of bone loss, patients with risk factors should be offered bisphosphonates or denosumab. Individualization of treatment is crucial. Consideration should be given to therapy effects on quality of life, and strategies for controlling associated symptoms should be offered.

Hypertension Drug Therapy

Hypertension is still the number one global killer. No matter what causes are, lowering blood pressure can significantly reduce cardiovascular complications, cardiovascular death, and total death. Unfortunately, some hypertensive individuals simply do not know having hypertension. Some knew it but either not being treated or treated but blood pressure does not achieve goal. The reasons for inadequate control of blood pressure are many. One important reason is that we are not very familiar with antihypertensive agents and less attention has been paid to comorbidities, complications as well as the hypertension-modified target organ damage in patients with hypertension. The right antihypertensive drug was not given to the right hypertensive patients at right time. This reviewer studied comprehensively the literature, hopefully that the review will help improve antihypertensive drug selection and antihypertensive therapy.

Acute Management of Hypertension Following Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is responsible for approximately 15% of strokes annually in the United States, with nearly 1 in 3 of these patients dying without ever leaving the hospital. Because this disproportionate mortality risk has been stagnant for nearly 3 decades, a main area of research has been focused on the optimal strategies to reduce mortality and improve functional outcomes. The acute hypertensive response following ICH has been shown to facilitate ICH expansion and is a strong predictor of mortality. Rapidly reducing blood pressure was once thought to induce cerebral ischemia, though has been found to be safe in certain patient populations. Clinicians must work quickly to determine whether specific patient populations may benefit from acute lowering of systolic blood pressure (SBP) following ICH. This review provides nurses with a summary of the available literature on blood pressure control following ICH. It focuses on intravenous and oral antihypertensive medications available in the United States that may be utilized to acutely lower SBP, as well as medications outside of the antihypertensive class used during the acute setting that may reduce SBP.

The Effects of Sympathetic Inhibition on Metabolic and Cardiopulmonary Responses to Exercise in Hypoxic Conditions

OBJECTIVE

Pre-exertion skeletal muscle glycogen content is an important physiological determinant of endurance exercise performance: low glycogen stores contribute to premature fatigue. In low-oxygen environments (hypoxia), the important contribution of carbohydrates to endurance performance is further enhanced as glucose and glycogen dependence is increased; however, the insulin sensitivity of healthy adult humans is decreased. In light of this insulin resistance, maintaining skeletal muscle glycogen in hypoxia becomes difficult, and subsequent endurance performance is impaired. Sympathetic inhibition promotes insulin sensitivity in hypoxia but may impair hypoxic exercise performance, in part due to suppression of cardiac output. Accordingly, we tested the hypothesis that hypoxic exercise performance after intravenous glucose feeding in a low-oxygen environment will be attenuated when feeding occurs during sympathetic inhibition.

METHODS

On 2 separate occasions, while breathing a hypoxic gas mixture, 10 healthy men received 1 hour of parenteral carbohydrate infusion (20% glucose solution in saline; 75 g), after which they performed stationary cycle ergometer exercise (~65% maximal oxygen uptake) until exhaustion. Forty-eight hours before 1 visit, chosen randomly, sympathetic inhibition via transdermal clonidine (0.2 mg/d) was initiated.

RESULTS

The mean time to exhaustion after glucose feeding both with and without sympathetic inhibition was not different (22.7 ± 5.4 minutes vs 23.5 ± 5.1 minutes; P = .73).

CONCLUSIONS

Sympathetic inhibition protects against hypoxia-mediated insulin resistance without influencing subsequent hypoxic endurance performance.

Refining the anesthesia management of the face-lift patient: lessons learned from 1089 consecutive face lifts

BACKGROUND

The importance of anesthetic technique is often underappreciated in face-lift procedures and is sparsely written about in the literature. Appropriate control of blood pressure, anxiety, pain, and nausea is essential for reducing the complications of face lift, primarily, hematoma risk. This study discusses the standard anesthetic protocol provided at the authors' institution and describes the preoperative, intraoperative, and postoperative management of face-lift patients resulting in low hematoma and complication rates.

METHODS

One thousand eighty-nine patients who underwent face-lift procedures performed by a single surgeon (R.J.R) were included in a retrospective chart review following institutional review board approval. Patient demographics, operative data including additional ancillary procedures, and the anesthesia regimen were recorded. In addition, postoperative complications and reoperation rates were documented.

RESULTS

Between 1990 and 2013, 1089 face-lift procedures were performed. Of these, 10 patients developed postoperative hematomas. Benzodiazepines were commonly administered preoperatively to reduce anxiety level. Intraoperatively, a specific regimen and combination of inhalation agents, neuromuscular blockers, antiemetics, antihypertensives, and narcotics was given to control the ease of induction and emergence from anesthesia. Postoperatively, nausea, vomiting, anxiety, pain, and hypertension were treated as needed.

CONCLUSIONS

The described protocol is safe and has been instituted at the authors' facility for approximately 20 years. The benefit of this regimen is related to the synergy of combination therapy. It is successful in reducing patient anxiety and pain, controlling blood pressure and postoperative emesis, and subsequently results in a reduced risk of hematoma.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Transdermal patches: history, development and pharmacology

Transdermal patches are now widely used as cosmetic, topical and transdermal delivery systems. These patches represent a key outcome from the growth in skin science, technology and expertise developed through trial and error, clinical observation and evidence-based studies that date back to the first existing human records. This review begins with the earliest topical therapies and traces topical delivery to the present-day transdermal patches, describing along the way the initial trials, devices and drug delivery systems that underpin current transdermal patches and their actives. This is followed by consideration of the evolution in the various patch designs and their limitations as well as requirements for actives to be used for transdermal delivery. The properties of and issues associated with the use of currently marketed products, such as variability, safety and regulatory aspects, are then described. The review concludes by examining future prospects for transdermal patches and drug delivery systems, such as the combination of active delivery systems with patches, minimally invasive microneedle patches and cutaneous solutions, including metered-dose systems.

Programmable transdermal clonidine delivery through voltage-gated carbon nanotube membranes

Oral dosage forms and traditional transdermal patches are inadequate for complex clonidine therapy dosing schemes, because of the variable dose/flux requirement for the treatment of opioid withdrawal symptoms. The purpose of this study was to evaluate the in vitro transdermal flux changes of clonidine in response to alterations in carbon nanotube (CNT) delivery rates by applying various electrical bias. Additional skin diffusion studies were carried out to demonstrate the therapeutic feasibility of the system. This study demonstrated that application of a small electrical bias (-600 mV) to the CNT membrane on the skin resulted in a 4.7-fold increase in clonidine flux as compared with no bias (0 mV) application. The high and low clonidine flux values were very close to the desired variable flux of clonidine for the treatment of opioid withdrawal symptoms. Therapeutic feasibility studies demonstrated that CNT membrane served as the rate-limiting step to clonidine diffusion and lag and transition times were suitable for the clonidine therapy. Skin elimination studies revealed that clonidine depletion from the skin would not negatively affect clonidine therapy. Overall, this study showed that clonidine administration difficulties associated with the treatment of opiate withdrawal symptoms can be reduced with the programmable CNT membrane transdermal system.

Dexmedetomidine infusion associated with transient adrenal insufficiency in a pediatric patient: a case report

Dexmedetomidine is a highly selective α₂-adrenoceptor agonist used for sedation due to its anxiolytic and analgesic properties without respiratory compromise. Due to its structural similarity to etomidate, there has been concern that dexmedetomidine may cause adrenal insufficiency. This concern was initially supported by animal studies, but subsequent human studies demonstrated mixed results. We describe the case of transient adrenal insufficiency in a 1-year-old male who presented with 24% total body surface 2nd degree burns. He required sedation with a prolonged, high-dose dexmedetomidine infusion with a peak infusion dose of 2.7 mcg/kg/hr and duration of 6.5 days. The patient developed lethargy and hypotension four days after discontinuation of his infusion. He had a random cortisol level which was low at 0.4 mcg/dL, and the concern for adrenal suppression was confirmed with an ACTH stimulation test with the baseline cortisol of 0.4 mcg/dL and inappropriate 60 minute post-ACTH stimulation cortisol of 7.8 mcg/dL. While further studies will be needed to clarify the risk of adrenal suppression secondary to dexmedetomidine, this case suggests that caution should be taken when administering dexmedetomidine to pediatric patients and highlights the need for future studies to look at appropriate dosing and duration of dexmedetomidine infusions.

Opioid-free perioperative analgesia for hemicolectomy in a patient with opioid-induced delirium: a case report and review of the analgesic efficacy of the alpha-2 agonist agents

Surgical pain in patients with documented opioid-induced delirium can be difficult to treat. We present a case of a patient undergoing laparoscopic hemicolectomy effectively treated with an opioid-free, alpha-2 adrenoreceptor agonist analgesic regimen.

CASE REPORT

A 21-year-old woman with persistent abdominal pain presented to the operating room for laparoscopic hemicolectomy for redundant right colon. Her medical history included a recently diagnosed postoperative opioid-induced delirium. Epidural infusion with local anesthetic offered partial pain relief with sensory levels of T9-L2. With the addition of dexmedetomidine infusion in the immediate postoperative period, the patient was comfortable with pain scores of 1 to 2/10 on Numerical Rating Scale (NRS). On postoperative day 1, the infusion was discontinued and the clonidine, 12 μg/hours was added to the epidural bupivacaine. With increased sedation 48 hours later, neuraxial clonidine was discontinued in favor to transdermal clonidine 0.1 mg/week, which was maintained until hospital discharge. Pain scores were maintained at 2 to 3/10 on NRS for the next 3 days when increased abdominal distention because of abscess formation rendered a new surgical intervention. The analgesia for the exploratory laparoscopy was maintained using epidural clonidine and bupivacaine infusion as well as intravenous dexmedetomidine, which were maintained another 2 days. Pain scores remained minimal until discharged home 3 day later.

DISCUSSION

Nonopioid analgesic regimens are beneficial in patients at risk of postoperative cognitive dysfunction attributable to opioids. Successful postoperative analgesia was achieved in our patient by alternating various routes of administration of alpha-2 adrenoreceptor agonists.

Pharmacologic Issues in treating hypertension in CKD

Antihypertensive drugs are prescribed to patients with CKD to slow down the rate of loss of residual kidney function; to reduce proteinuria, when present; and to protect other target organs from damage that is mediated by elevated blood pressure (BP). In most patients, a diuretic and a renin system blocking drug, such as an angiotensin-converting enzyme inhibitor, angiotensin receptor antagonist, or an aldosterone receptor antagonist are used. Often, 3 or more drugs are needed to achieve BP goals. Many drugs are eliminated through the kidney and in some cases dosage reductions are advisable to avoid adverse effects from high levels of medication. This article will review the various classes of antihypertensive drugs used in the management of high BP in patients with CKD, with an emphasis on pitfalls that arise when kidney function is impaired.

Using explicit criteria to evaluate the quality of prescribing in elderly Italian outpatients: a cohort study

BACKGROUND AND OBJECTIVE

Inappropriate prescribing in the elderly population is a well-recognized problem in public health. The Beers criteria have been widely used to evaluate the quality of prescribing for the elderly. However, because the Beers criteria were developed in the United States, they are not fully applicable in Italy. The purpose of this study was to establish explicit criteria for potentially inappropriate medication prescribing (PIP) for the elderly and assess the prevalence of and factors associated with PIP among elderly residents in the Local Health Unit of Parma, Italy according to the developed criteria.

METHODS

A nine-member expert panel was convened to identify a list of inappropriate medications reflecting the Italian prescribing habits. The panel decided to refine and update the 2002 Beers criteria. Consensus through a Nominal Group Technique was reached to classify the identified 23 inappropriate medications into three categories: 17 medications to be always avoided, three medications rarely appropriate, and three medications with some indications but often misused. A retrospective cohort study using the 2006 Parma Local Health Unit automated outpatient prescriptions database was conducted. The cohort comprised 91 741 elderly individuals >or=65 years with at least one prescription medication. PIP was defined as having a prescription claim for at least one inappropriate medication.

RESULTS AND DISCUSSION

A total of 23 662 elderly in the cohort (25.8%) had at least one PIP. Of these, 14.1% received prescriptions for two medications of concern, and 2.0% for three or more. Using the expert panel's categories, 59.2% of the elderly receiving PIP had prescriptions for drugs that should always be avoided, 33.9% for rarely appropriate drugs, and 19.1% for drugs that have some indications but are often misused. Non-steroidal anti-inflammatory drugs (35.7% of subjects) were the most frequently occurring PIP, followed by ticlopidine (17.6%), doxazosin (15.5%), and amiodarone (13.6%). Female, older age, overall number of drugs prescribed, greater number of chronic conditions were factors associated with greater odds of receiving PIP.

CONCLUSION

Via the developed criteria, the study corroborates that PIP among elderly outpatients is a substantial issue in Parma Local Health Unit, Italy. Knowledge of the prevalence of PIP and associated factors should gear efforts to develop strategies to reduce PIP in outpatient settings in Italy.

Management of hypertension in the outpatient setting

The treatment of hypertension on an outpatient basis should be approached in a systematic manner. The diagnosis of hypertension should always be verified first before treatment is initiated and, where indicated, a workup should be done. Lifestyle modifications should be considered in all patients with hypertension. Blood pressure can be brought to goal in the majority of patients if antihypertensive medications are correctly dosed or combined. As blood pressure is brought to goal in the patient with hypertension, ongoing attention should be directed to long-term adherence to therapy.

Centrally acting antihypertensive agents: an update

Centrally acting agents stimulate alpha(2) receptors and/or imadozoline receptors on adrenergic neurons situated within the rostral ventrolateral medulla and, in so doing, sympathetic outflow is reduced. Centrally acting agents also stimulate peripheral alpha(2) receptors, which, for the most part, is of marginal clinical significance. Central a agonists have had a lengthy history of use, starting with alpha-methyldopa, which has had a dramatic decline in use, in part, because of bothersome side effects. Patients who require multidrug therapy with otherwise resistant hypertension, such as diabetic and/or renal failure patients, are typically responsive to these drugs, as are patients with sympathetically driven forms of hypertension. Perioperative forms of hypertension respond well to clonidine, a circumstance where the additional anesthesia- and analgesia-sparing effects of this drug may offer additional clinical benefits. Clonidine can be used adjunctively with other more traditional therapies in heart failure, particularly when hypertension is present. Sustained-release moxonidine, however, is associated with early mortality and morbidity when used in patients with heart failure. Escalating doses of drugs in this class often give rise to salt and water retention, in which case diuretic therapy becomes a valuable adjunctive therapy.

Current and emerging pharmacotherapies for treating tobacco dependence

Tobacco dependence remains the leading cause of death and disease in the US and a major cause of mortality around the world, yet 1 out of 5 American adults smoke and 1.3 billion adults smoke worldwide. Nicotine replacement therapies (NRTs), bupropion and varenicline, are approved by the US FDA as first-line treatments for nicotine dependence. Clonidine and nortriptyline are recommended as second-line treatments by the Agency for Healthcare Research and Quality. Although recent data suggest that varenicline is superior to bupropion for treating nicotine dependence, a majority of smokers fail to maintain long-term abstinence from smoking using FDA-approved pharmacotherapies. Thus, continued investigation of novel medications for nicotine dependence remains a critical priority. Guided by research on multiple neurobiological mechanisms of nicotine dependence, several novel medications that mimic and/or attenuate nicotine's rewarding effects, or reduce nicotine withdrawal, are under investigation. Although existing data are limited or conflicting, there is some evidence for the efficacy of selegiline, fluoxetine, naltrexone and mecamylamine in certain subgroups of smokers. New research directions, such as fast-acting NRTs, the tailored use of NRTs for subtypes of smokers, and pharmacogenetics, hold promise for new treatment approaches and, ultimately, for reducing rates of tobacco use in the US and worldwide.