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DIANABOL Third Degree Pharma Co
Overview of Anabolic–androgenic Steroids (AAS) – "Steroids"
Category Key Points
What they are Synthetic compounds derived from testosterone that combine androgenic (male‑sex hormone) and anabolic (muscle‑building) effects.
Common names "Steroids," "Anabolic Steroids," "AAS," "Performance‑Enhancing Drugs (PEDs)."
Medical uses Treatment of hormonal deficiencies, delayed puberty, muscle wasting, anemia, certain cancers, and other conditions where hormone replacement is needed.
Non‑medical use Bodybuilding, athletic performance enhancement, and as a perceived shortcut to increased size or strength.
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1. How Steroids Work in the Body
Step Process Key Players
1. Administration Oral pills, injections, creams, gels. Dexamethasone (a steroid).
2. Absorption & Distribution Enter bloodstream → travel to target tissues. Blood plasma, lipoproteins.
3. Receptor Binding Steroid molecules bind to intracellular receptors (glucocorticoid or mineralocorticoid). Glucocorticoid receptor (GR), Mineralocorticoid receptor (MR).
4. Transcriptional Activation Complex moves into nucleus → binds DNA response elements. Hormone Response Elements (HREs) on promoters.
5. Gene Regulation Upregulate or downregulate target genes; modulate proteins such as cytokines, enzymes. NF-κB inhibition, COX-2 suppression.
6. Physiological Outcome Anti-inflammatory effect, immune modulation, electrolyte balance changes. Decrease in inflammation, reduction of edema, altered blood pressure.
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4. Key Points for the Exam
Mechanism of Action (MoA)
- Steroid hormones act as intracellular transcription regulators, modulating gene expression by binding to nuclear receptors.
- Their anti‑inflammatory effect largely stems from inhibition of pro‑inflammatory cytokines and suppression of the NF‑κB pathway.
Therapeutic Use
- Widely used in inflammatory diseases (e.g., rheumatoid arthritis, asthma) and as immunosuppressants in transplant patients.
Side‑Effect Profile
- Chronic systemic side effects: osteoporosis, hyperglycemia/diabetes, hypertension, Cushingoid features.
- Local ocular adverse events: increased intraocular pressure, cataract formation, corneal thinning and ulceration (especially with prolonged use or high concentrations).
- Systemic absorption via ocular route is less common but can still occur; thus systemic side effects remain a concern.
Clinical Significance
- The potential for severe local adverse events (e.g., corneal perforation) necessitates careful monitoring, especially in patients with pre‑existing ocular surface disease or high cumulative exposure.
- Understanding the spectrum of adverse events helps clinicians balance therapeutic benefits against risks and informs informed consent discussions.
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5. Practical Implications & Recommendations
Clinical Scenario Considerations Action Points
Long‑term anti‑VEGF therapy for AMD or DME High cumulative exposure; risk of corneal complications in patients with dry eye, contact lens wearers, or ocular surface disease. Screen for ocular surface health before initiating therapy; consider baseline tear film assessment.
Patients on frequent intravitreal injections Potential for cumulative damage beyond individual injection toxicity. Schedule regular slit‑lamp exams; educate patients about symptoms of corneal irritation.
Use of adjunctive therapies (e.g., steroids) May exacerbate ocular surface issues; increased inflammation risk. Monitor intraocular pressure and ocular surface status closely.
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3. Proposed Study Design to Investigate Corneal Toxicity
Title
"Prospective Cohort Study of Corneal Endothelial Cell Loss in Patients Receiving Repeated Intravitreal Anti‑VEGF Therapy"
Aspect Details
Study Population Adults ≥ 18 yr with retinal diseases (e.g., AMD, diabetic retinopathy) scheduled for anti‑VEGF therapy. Exclude patients with pre‑existing corneal endothelial disease or prior corneal surgery.
Sample Size 300 eyes from ~150 patients to allow detection of a 5 % difference in cell density with 80 % power at α=0.05, accounting for dropout.
Study Design Prospective longitudinal cohort; each eye serves as its own control over time.
Exposure Variables Number of injections, injection interval (weeks), cumulative volume, type of anti‑VEGF agent, pre‑ and post‑injection intraocular pressure measurements.
Outcome Measures Primary: Change in corneal endothelial cell density (cells/mm²) measured by specular microscopy at baseline, 6 mo, 12 mo, 24 mo. Secondary: Central corneal thickness, presence of corneal edema or decompensation, patient-reported visual symptoms.
Statistical Analysis Mixed-effects linear regression models to assess the association between exposure variables and endothelial cell loss over time, adjusting for baseline density, age, sex, cataract status, and comorbidities. Interaction terms to explore effect modification by intraocular pressure elevation or lens status. Sensitivity analyses excluding eyes with significant ocular trauma or surgery unrelated to injection.
Ethical Considerations Institutional review board approval; informed consent obtained for data collection; adherence to privacy regulations (e.g., HIPAA).
This prospective observational study would provide robust evidence on the safety profile of intravitreal injections, specifically addressing concerns about endothelial cell loss and corneal complications.
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3. Comparative Analysis: Intravitreal Versus Subconjunctival Injections
Parameter Intravitreal Injection (IVI) Subconjunctival Injection (SC)
Procedure Aseptic puncture of the sclera, insertion of a fine needle into vitreous cavity. Requires topical anesthesia, povidone-iodine prep. Insertion of a needle into subconjunctival space under ocular surface; simpler technique.
Anatomical Targets Direct delivery to posterior segment (vitreous and retina). Delivery primarily to anterior segment tissues (cornea, conjunctiva).
Drug Distribution High concentration in vitreous, limited diffusion to anterior chamber unless drug is lipophilic or aqueous-soluble. Drug remains in subconjunctival space; may reach anterior segment via episcleral veins.
Potential Complications Retinal detachment, vitreous hemorrhage, endophthalmitis, globe perforation, IOP spikes, cataract formation. Corneal epithelial defects, superficial ocular surface irritation, mild inflammation.
Invasiveness Highly invasive; requires skilled ophthalmic injection technique and sterile environment. Minimally invasive; topical application with limited systemic absorption.
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4. Recommendations
If a topical formulation of the new drug is feasible (e.g., sufficient ocular surface penetration, minimal systemic exposure), it should be preferred over intravitreal injection due to lower invasiveness and reduced risk profile.
When therapeutic concentrations must be achieved in the posterior segment (e.g., retinal disease), consider alternative delivery routes such as:
- Sustained-release implants placed subretinally or suprachoroidally,
- Intracameral injections with extended release formulations,
- Ocular surface–to‑posterior segment drug transfer via permeation enhancers.
Intravitreal injection should be reserved for cases where no less invasive route can achieve therapeutic efficacy and should involve:
- Pre‑procedural screening (e.g., ultrasound biomicroscopy, slit lamp exam),
- Sterile technique with povidone‑iodine preparation,
- Post‑injection prophylactic antibiotic drops if indicated.
Post‑procedure monitoring must include assessment for intraocular pressure spikes, inflammatory response, and infection.
5. Documentation
Record the chosen route of administration in the patient’s chart, including rationale and any relevant pre‑procedure assessments.
Document informed consent, explaining risks associated with each potential route.
Log all procedural details (date/time, instrument used, sterility measures) for quality‑control purposes.
6. Review & Updates
The SOP will be reviewed annually or sooner if new evidence emerges that impacts the choice of injection route. Feedback from clinical staff should be solicited to refine procedures and address practical challenges.
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Prepared by:
Your Name, Clinical Coordinator
Date
Approved by:
Approver’s Name, Head of Ophthalmology
Date
Version 1.0 – Effective Date: Insert Date - https://codes.tools.asitavsen.com/keenangaunt55
