Hormonal contraceptives may be affected by concomitant medicines that alter steroid-hormone metabolism. Rifamycin antibiotics are particularly important because some members of this class, especially rifampicin (rifampin), strongly induce drug-metabolizing enzymes and can reduce systemic exposure to contraceptive hormones. This review summarizes pharmacokinetic, pharmacodynamic, clinical, and guideline evidence concerning interactions between rifamycin antibiotics and hormonal contraceptives. Evidence is strongest for combined oral contraceptives (COCs), for which rifampicin has been associated with reductions in ethinyl estradiol and progestin exposure and, in some studies, increased markers of ovarian activity. Rifabutin also alters contraceptive pharmacokinetics, but generally to a lesser extent than rifampicin. Evidence concerning etonogestrel implants has expanded: rifampicin reduces serum etonogestrel concentrations and has been associated with altered ovarian-activity biomarkers, and a published case report described pregnancy during concomitant rifampicin therapy. Evidence for non-oral systems is more heterogeneous. A 2025 study of a segesterone acetate/ethinyl estradiol vaginal contraceptive system found reduced ethinyl estradiol exposure but no significant change in segesterone acetate exposure, illustrating why interactions should be assessed for the specific contraceptive formulation. Rifaximin and rifalazil have not demonstrated clinically important pharmacokinetic effects on ethinyl estradiol in the studies reviewed. Clinical management should therefore consider the individual rifamycin, contraceptive formulation, duration of therapy, and current contraceptive guidance rather than treating all rifamycins as interchangeable.

Polycystic ovary syndrome (PCOS), also referred to as polyendocrine metabolic ovarian syndrome (PMOS), is a common endocrine and metabolic disorder characterized by hyperandrogenism, insulin resistance, chronic in-flammation, oxidative stress, and reproductive dysfunction. Conventional treatments primarily target individual symptoms but may be limited by poor bioavailability, adverse effects, and variable therapeutic response. Nanocarrier-based drug delivery systems offer promising strategies for improving drug solubility, stability, bio-availability, controlled release, and targeted delivery. This review summarizes major nanocarrier systems, thera-peutic targets, preclinical evidence, and emerging approaches for PCOS management. It also discusses safety concerns, translational challenges, and future prospects for the clinical application of nanomedicine in PCOS.

Polycystic ovary syndrome (PCOS), now renamed polyendocrine metabolic ovarian syndrome (PMOS), is a common endocrine and metabolic disorder that affects fertility, metabolic health and quality of life. Available drugs treat isolated features of the syndrome and are often limited by side effects, incomplete response and poor adherence. Plant-derived compounds such as curcumin, quercetin, resveratrol, berberine and naringenin act on several pathogenic pathways at once, including insulin signalling, inflammation and oxidative stress, but their clinical use is restricted by low solubility, rapid metabolism and poor oral bioavailability. Nano-formulation is increasingly used to overcome these barriers. In the second generation of delivery systems is being developed that adds ovarian targeting, cell-membrane camouflage and release that is triggered by the diseased microenvironment, particularly by reactive oxygen species. This review covers the rationale for phytochemical nanomedicine in PCOS, the nanocarriers and stabilisation strategies used, the preclinical evidence, and the emerging targeted and stimuli-responsive approaches. Examine the local routes such as vaginal delivery, computational formulation design, and the safety, model and regulatory barriers that still separate these systems from the clinic. Most evidence comes from letrozole-induced rodents, and much of the stimuli-responsive design knowledge comes from cancer research rather than from PCOS itself. Standardised models, reproductive toxicology and early clinical trials are the priorities for the field.

The cosmetic industry is increasingly moving toward multifunctional formulations that combine cosmetic benefits with the delivery of biologically active ingredients. However, the effective delivery of these ingredients to the skin can be challenging due to factors such as poor stability, degradation and limited skin penetration. This has encouraged the development of advanced delivery systems designed to improve the protection, stability and delivery of cosmetic actives. Biomimetic delivery systems, which are inspired by natural biological structures and processes, have gained attention in advanced cosmetics because they can help protect active ingredients and improve their delivery and performance in topical formulations. Various delivery platforms including liposomes, niosomes, nanoemulsions, solid lipid nanoparticles, nanostructured lipid carriers and polymeric nanocarriers have been investigated for cosmetic applications. In addition, smart or stimuli-responsive delivery systems have gained attention for their ability to respond to specific stimuli, such as pH, temperature, enzymes and light, thereby enabling controlled or triggered release of active ingredients. This review provides an overview of recent advances in biomimetic and smart delivery systems for cosmetics and cosmeceuticals, focusing on their mechanisms, applications, advantages, limitations, safety considerations and future perspectives.