GLP-1 & Telehealth
Medical Glossary

GLP-1 (Glucagon-Like Peptide-1) is a hormone naturally released by the intestines after eating. It signals fullness to the brain via the hypothalamus, slows gastric emptying, and stimulates insulin secretion in a glucose-dependent manner. GLP-1 receptor agonist medications like semaglutide and tirzepatide mimic this hormone pharmacologically, producing significant, clinically-documented weight loss that no diet program or supplement has matched in clinical trials. GLP-1 therapy is prescription-only and requires evaluation by a licensed medical provider.

Semaglutide is a GLP-1 receptor agonist medication used for chronic weight management and type 2 diabetes. It is the active ingredient in FDA-approved Ozempic (approved for type 2 diabetes) and Wegovy (approved for chronic weight management). Compounded semaglutide uses the same active pharmaceutical ingredient (API) but is not FDA-approved as a finished drug product and is not interchangeable with any FDA-approved product. In the landmark STEP 1 clinical trial published in the New England Journal of Medicine (2021, PMID 33567185), semaglutide 2.4mg produced an average of 15–17% body weight loss over 68 weeks. Semaglutide is administered as a once-weekly subcutaneous injection and requires a prescription from a licensed medical provider. Ozempic® and Wegovy® are registered trademarks of Novo Nordisk A/S. Open Water Rx is not affiliated with Novo Nordisk.

Tirzepatide is a dual GIP/GLP-1 receptor agonist medication used for chronic weight management and type 2 diabetes. It is the active ingredient in FDA-approved Mounjaro (approved for type 2 diabetes) and Zepbound (approved for chronic weight management). Unlike semaglutide, which activates only the GLP-1 receptor, tirzepatide activates both GIP (Glucose-Dependent Insulinotropic Polypeptide) and GLP-1 receptors simultaneously. This dual mechanism produces significantly greater appetite suppression and metabolic improvement. In the SURMOUNT-1 clinical trial published in the New England Journal of Medicine (2022, PMID 35658024), tirzepatide 15mg produced an average of 22.5% body weight loss over 72 weeks — the highest weight loss ever recorded in a pharmaceutical clinical trial. Compounded tirzepatide uses the same API but is not FDA-approved as a finished drug product. Mounjaro® and Zepbound® are registered trademarks of Eli Lilly and Company. Open Water Rx is not affiliated with Eli Lilly.

GIP (Glucose-Dependent Insulinotropic Polypeptide) is a gut hormone secreted by K-cells in the small intestine in response to food intake. It stimulates insulin secretion from the pancreas in a glucose-dependent manner and plays a role in fat storage, energy metabolism, and bone metabolism. GIP receptors are also found in the brain, where GIP signaling may contribute to appetite regulation. Tirzepatide is a dual GIP/GLP-1 receptor agonist that activates both GIP and GLP-1 receptors simultaneously, producing greater weight loss than GLP-1 agonists alone. The synergistic effect of dual receptor activation is believed to be responsible for tirzepatide's superior clinical efficacy compared to semaglutide.

A compounding pharmacy prepares customized medications for individual patients when commercially available products do not meet a patient's specific clinical needs — for example, when a specific dosage strength, formulation, or delivery method is not available in the commercially manufactured product. Section 503A of the Federal Food, Drug, and Cosmetic Act governs traditional compounding pharmacies that prepare medications based on individual patient prescriptions. Section 503B governs outsourcing facilities that may produce larger batches without individual prescriptions. Compounded medications are not FDA-approved finished drug products and have not been evaluated by the FDA for safety, efficacy, or quality. Open Water Rx works exclusively with licensed, FDA-registered compounding pharmacies operating under Section 503A or 503B. Partner pharmacies use only the base active pharmaceutical ingredient (API), not salt derivatives (e.g., not semaglutide sodium or semaglutide acetate).

Body Mass Index (BMI) is a numerical measure calculated from a person's height and weight (weight in kg divided by height in meters squared). BMI is used as a screening tool for weight categories: underweight (below 18.5), normal weight (18.5–24.9), overweight (25–29.9), and obese (30 or higher). For GLP-1 weight loss therapy, the general eligibility criteria are: BMI of 30 or higher, OR BMI of 27 or higher with at least one weight-related health condition such as type 2 diabetes, hypertension, dyslipidemia, or sleep apnea. Final eligibility is always determined by an independent licensed medical provider based on the individual patient's complete health profile. BMI is a screening tool, not a diagnostic measure, and does not account for muscle mass, bone density, or fat distribution.

Telehealth is the delivery of healthcare services using digital communications technology — including secure online forms, asynchronous messaging, and synchronous video consultations — allowing patients to receive medical care remotely without in-person clinic visits. Open Water Rx is a 100% telehealth platform connecting patients with independent licensed medical providers for GLP-1 weight loss, NAD+ longevity, and men's health programs. In most states, the entire process — health evaluation, provider review, prescription, and medication delivery — can be completed without any in-person visit. Some states require a synchronous (live video) initial visit with a licensed provider before a prescription can be issued. Telehealth regulations vary by state and are subject to change.

A Valid Patient-Provider Relationship (VPPPR) is a legally required relationship between a patient and a licensed medical provider that must be established before a prescription can be issued. In telehealth, establishing a VPPPR typically requires a thorough health evaluation covering the patient's medical history, current medications, health conditions, and treatment goals. Some states additionally require a synchronous (live video) initial visit with the licensed provider before a prescription can be issued. Open Water Rx requires a VPPPR before any prescription is issued. All prescribing decisions are made solely by independent licensed medical providers based on the individual patient's health profile. Open Water Rx does not direct or influence those decisions.

NAD+ (Nicotinamide Adenine Dinucleotide) is a coenzyme found in all living cells that plays a critical role in energy metabolism, DNA repair, gene expression, and cellular aging. NAD+ is essential for the function of sirtuins — proteins that regulate cellular health and longevity. NAD+ levels naturally decline with age, which is associated with reduced energy, slower recovery, and increased susceptibility to age-related conditions. NAD+ therapy involves supplementing this coenzyme through IV infusion, subcutaneous injection, nasal spray, or oral formulations to support cellular energy, recovery, and healthy aging. Compounded NAD+ is not FDA-approved as a finished drug product. Open Water Rx offers clinician-reviewed NAD+ programs through licensed, FDA-registered compounding pharmacies.

Sermorelin is a synthetic peptide analog of growth hormone-releasing hormone (GHRH) that stimulates the pituitary gland to produce and release growth hormone (GH). Unlike direct growth hormone supplementation, sermorelin works by stimulating the body's own natural growth hormone production, which may result in a more physiological response. Sermorelin is used in longevity and anti-aging programs to support muscle mass, energy levels, sleep quality, body composition, and recovery. Compounded sermorelin is not FDA-approved as a finished drug product. Open Water Rx offers clinician-reviewed sermorelin programs through licensed, FDA-registered compounding pharmacies.

B12 MIC is a lipotropic injection combining Vitamin B12 (cobalamin) with Methionine, Inositol, and Choline — compounds that support fat metabolism, liver function, and energy production. Methionine is an essential amino acid that helps break down fats. Inositol supports insulin signaling and fat metabolism. Choline is essential for liver function and fat transport. B12 supports energy metabolism and neurological function. B12 MIC injections are used in metabolic health and weight management programs to support energy, metabolism, and liver health. Compounded B12 MIC is not FDA-approved as a finished drug product.

Asynchronous telehealth (async care) is a model of healthcare delivery where patients and providers do not interact in real time. Instead, patients submit health information, photos, or questionnaires through a secure platform, and licensed providers review and respond on their own schedule — typically within 24–72 hours. This model is more convenient for patients (no scheduling, no waiting rooms) and allows providers to review cases more thoroughly. Open Water Rx uses asynchronous telehealth for initial evaluations, follow-up reviews, and ongoing care. Some states require a synchronous (live video) initial visit before a prescription can be issued, even in an async-first platform.

Section 503A of the Federal Food, Drug, and Cosmetic Act governs traditional compounding pharmacies that prepare medications based on individual patient prescriptions from licensed practitioners. 503A pharmacies must comply with state pharmacy laws and USP standards. They may not compound medications that are essentially copies of commercially available FDA-approved drugs unless there is a documented clinical difference. Compounded medications from 503A pharmacies are not FDA-approved finished drug products. Open Water Rx works with licensed, FDA-registered 503A compounding pharmacies.

Section 503B of the Federal Food, Drug, and Cosmetic Act governs outsourcing facilities — compounding pharmacies that register with the FDA and may produce larger batches of compounded medications without individual patient prescriptions. 503B facilities are subject to FDA inspection and must comply with Current Good Manufacturing Practice (CGMP) standards. Medications from 503B facilities are not FDA-approved finished drug products but are subject to more rigorous quality standards than traditional 503A pharmacies. Open Water Rx works with licensed, FDA-registered 503A and 503B compounding facilities.

The STEP 1 (Semaglutide Treatment Effect in People with Obesity) trial was a Phase 3 randomized controlled trial published in the New England Journal of Medicine in 2021 (Wilding et al., PMID 33567185). The trial enrolled 1,961 adults with obesity (BMI ≥30) or overweight (BMI ≥27) with at least one weight-related condition. Participants received either semaglutide 2.4mg once weekly or placebo for 68 weeks, alongside lifestyle intervention. Results: participants on semaglutide lost an average of 14.9% of body weight (approximately 15–17% in clinical practice), compared to 2.4% in the placebo group. This represented the highest weight loss ever recorded for a GLP-1 receptor agonist at the time of publication.

The SURMOUNT-1 trial was a Phase 3 randomized controlled trial published in the New England Journal of Medicine in 2022 (Jastreboff et al., PMID 35658024). The trial enrolled 2,539 adults with obesity (BMI ≥30) or overweight (BMI ≥27) with at least one weight-related condition. Participants received tirzepatide at doses of 5mg, 10mg, or 15mg once weekly, or placebo, for 72 weeks. Results: participants on tirzepatide 15mg lost an average of 22.5% of body weight — the highest weight loss ever recorded in a pharmaceutical clinical trial. Participants on 10mg lost an average of 21.4%, and those on 5mg lost an average of 16.0%. The placebo group lost an average of 2.4%.