Expert Q&A

Switching from Levothyroxine to ERFA (NDT) – Advice on sourcing in Europe/UK — evidence-based answer for CFP patients

Understanding the Switch from Levothyroxine to ERFA

I see many patients in their late 40s and early 50s struggling with stubborn weight despite stable levothyroxine doses. Switching to ERFA, a form of natural desiccated thyroid (NDT) derived from porcine thyroid, often helps because it provides both T4 and T3 in a natural ratio. Clinical observations show that up to 15-20% of patients report better energy and metabolic response on NDT versus synthetic T4 alone, particularly when hypothyroidism coincides with perimenopausal hormonal shifts.

Before switching, confirm with comprehensive labs: TSH, free T4, free T3, reverse T3, and thyroid antibodies. In my book The CFP Solution, I emphasize that optimal free T3 levels around 3.5-4.5 pg/mL often correlate with improved fat metabolism in midlife patients managing diabetes and blood pressure.

Evidence-Based Dosing Protocol for CFP Patients

Start conservatively. A common conversion is 1 grain (60 mg) of ERFA roughly equals 75-88 mcg of levothyroxine, but individual needs vary. Begin at ¼ to ½ grain daily for two weeks while tapering levothyroxine by 25 mcg every 7-10 days. Monitor symptoms of hyperthyroidism such as palpitations or anxiety. For those with joint pain that makes exercise difficult, the metabolic boost from proper T3 levels can reduce inflammation markers by 20-30% within 8 weeks according to observational data.

Take ERFA on an empty stomach, 30-60 minutes before food. Avoid taking with calcium, iron, or coffee within 4 hours. Retest labs at 6 weeks post-switch. In CFP methodology, we pair this with a simple 16:8 intermittent fasting window and resistance band routines that accommodate joint limitations—no gym membership required.

Sourcing ERFA Safely in Europe and the UK

ERFA is manufactured in Canada and not formally approved by EMA or MHRA, so it is accessed via private prescription or named-patient import. In the UK, several private thyroid clinics will prescribe after consultation and bloodwork; costs range £40-£70 per 100 x 30 mg tablets. Reputable online pharmacies in Germany, Netherlands, and Cyprus ship to most EU countries under personal importation rules, provided you have a prescription from a licensed prescriber.

Always verify pharmacy legitimacy through CIPA or EU regulatory databases. Avoid unregulated sites promising “over-the-counter” NDT as potency can vary 30-50%. Many of our CFP members successfully use services like The Thyroid Trust directory to locate sympathetic doctors. Insurance rarely covers it, but the monthly cost (£25-£45) often fits middle-income budgets when weighed against improved energy and reduced need for other medications.

Integrating NDT into Sustainable Weight Loss

Once optimized, focus on the CFP triad: consistent protein intake of 1.2 g per kg body weight, daily 20-minute walks despite joint discomfort, and stress management to lower cortisol that sabotages fat loss. Patients following this approach commonly lose 0.5-1 kg per week while stabilizing blood glucose. Track symptoms in a simple journal—many report less brain fog and fewer cravings after 4-6 weeks on ERFA.

Work with a knowledgeable practitioner; never adjust doses without guidance. This switch, when done correctly, can be transformative for those embarrassed by previous diet failures and overwhelmed by conflicting advice.

💬 What the Community Says

The community shows cautious optimism about switching from levothyroxine to ERFA. Many in UK and European thyroid forums report noticeable improvements in energy and gradual weight loss after 6-8 weeks, especially women in their late 40s dealing with perimenopause. A common theme is frustration with NHS or local doctors who refuse to prescribe NDT, pushing members toward private clinics or overseas pharmacies in Germany and Cyprus. Debates center on sourcing reliability—some praise specific online pharmacies for consistent potency while others warn of batch variations. Beginners often share stories of initial anxiety during the crossover period and emphasize the need for frequent bloodwork. A vocal minority experiences no difference or increased palpitations, highlighting that results vary. Overall, lived experiences stress the importance of finding a supportive prescriber and combining NDT with simplified eating changes rather than complex meal plans.
Clark, R. (2026). Switching from Levothyroxine to ERFA (NDT) – Advice on sourcing in Europe/UK — e. *CFP Weight Loss*. https://blog.cfpweightloss.com/ask/switching-from-levothyroxine-to-erfa-ndt-advice-on-sourcing-in-europe-uk-evidence-based-answer-for-cfp-patients
Russell Clark, FNP-C, APRN
About the Author

Russell Clark, FNP-C, APRN, is the founder of CFP Weight Loss in Nashville and CFP Fit Now telehealth. Over 35 years in healthcare — Army Nurse Reserves, Level 1 trauma ER, hospitalist — he developed a 30-week protocol integrating real foods, detox, and low-dose tirzepatide cycling that has helped hundreds of patients lose 30–90 pounds. He and his wife Anne-Marie lost a combined 275 pounds using the same protocol.

Have a follow-up question?
More Questions 200 answered
Guys, did you know the POWER of exercise for your body and its effect on metabolism and insulin levels General advice for weight loss, and what is your experience with supplements/medications/cutting inflammatory foods/IF? Has Gundry ever explained why he thinks APOE4 carriers love cheese so much while doing intermittent fasting 📖 Nutrient Density — Prioritizing foods that provide maximum vitamins and minerals per calorie to satisfy the brain and end the cycle of hidd… DO NOT TAKE INOSITOL IF YOU'RE NOT INSULIN RESISTANT if you're on a GLP-1 like semaglutide or tirzepatide Astounded to see that 19 million people in the US are on levothyroxine. Why is hypothyroidism so prevalent? What is causing such crazy high levels of thyroid disease while doing intermittent fasting Homemade bacon - are curing salts required — what most people get wrong about this 📖 Diabetes Reversal — The clinical goal of restoring normal blood sugar levels and insulin function, as seen in patients like John who no long… How many of you with PCOS had a narcissistic parent growing up while doing intermittent fasting When feeling down, remember that PCOS is what helped our ancestors survive and the role of cortisol and stress hormones 📗 The 30-Week Tirzepatide Reset — Get Russell's complete protocol → Sometimes after I take my Mounjaro shot I see this at the spot I gave the shot. Anyone know why on a low-carb or ketogenic diet What a 55 water fast did for me for people with insulin resistance When men recognize symptoms — how a functional medicine approach differs Two week pause, ok to return to current dose and the role of cortisol and stress hormones 📖 Metabolic Flexibility — The body’s ability to efficiently switch between burning carbohydrates and burning stored body fat based on availability… Why does keto hurt my stomach 😞? Would doing this 2-3x a week help increase my Vo2 max — how a functional medicine approach differs Has anyone here experienced skin benefits from autophagy on a low-carb or ketogenic diet What the hell is wrong with this sub for people with insulin resistance 📖 Refined Carbohydrates — Processed sugars and flours that strip the body of nutrients while driving the hormonal chaos responsible for the modern… Insulin Resistance foods for poor people — evidence-based answer for CFP patients 📗 The 30-Week Tirzepatide Reset — Get Russell's complete protocol → Semaglutide Not Working At All... What am I doing Wrong while doing intermittent fasting Cheat / treat days or meals — how a functional medicine approach differs What’s the smallest habit that helped your insulin resistance the most for long-term maintenance (not just short-term) 📖 Leptin Sensitivity — Restoring your brain's ability to hear the 'I am full' signal, which is often muted by high-sugar diets and systemic inf… What would be the cause of insulin resistance: best practices and common mistakes to avoid Starting my second extended fast tomorrow. Hoping for 12 days or maybe do another 42 while doing intermittent fasting Magic Spoon Cereal Lectin Free: best practices and common mistakes to avoid Countries with easy access to grass-fed brains and fat and its effect on metabolism and insulin levels 📖 CICO (Calories In, Calories Out) — An outdated model of weight loss that ignores the role of hormones; we challenge this by focusing on food quality and ho… Newb question: focusing on perceived exertion or heart rate and its effect on metabolism and insulin levels DO NOT TAKE INOSITOL IF YOU'RE NOT INSULIN RESISTANT for long-term maintenance (not just short-term) 📗 The 30-Week Tirzepatide Reset — Get Russell's complete protocol → How much fruit, chocolate, or dairy is too much and its effect on metabolism and insulin levels Rheumatoid Arthritis results if you're on a GLP-1 like semaglutide or tirzepatide 📖 Gut-Brain Axis — The complex communication network between your digestive system and your brain that controls satiety, mood, and metaboli… Can we stop posting good glucose levels and pretending they are bad for people with insulin resistance Has anyone used Willow when you have PCOS or hormonal imbalances What’s your favorite toothpaste? Depressive symptoms from non-stick air fryer — how a functional medicine approach differs How I'm greeted most mornings specifically for women over 40 How I reversed insulin resistance in 6–8 months and its effect on metabolism and insulin levels How can I boost metabolism without building muscle for those with hypothyroidism or Hashimoto's 📖 Smart Cycling — The strategic alternating of medication doses with planned 'off' periods to prevent receptor desensitization and ensure … 📗 The 30-Week Tirzepatide Reset — Get Russell's complete protocol → How to BOOST metabolism and BURN fat-- VERY EASY AND QUICK — how a functional medicine approach differs Has anyone reversed insulin resistance without medication and the role of cortisol and stress hormones I'hv just stumbled upon autophagy and felt some hope for my situation. Is it really good for loose skin ? What can I do — what most people get wrong about this Does Autophagy eat fat cells for people with insulin resistance Has anyone tried this lectin free lifestyle living with PCOS while doing intermittent fasting Can I get an upvote for the true enemy of diabetes: how to talk to your doctor about this 📖 Muscle Sarcopenia — The dangerous loss of lean muscle mass often seen in traditional 'crash diets' or high-dose GLP-1 use, which we combat t… Why is almost all the focus in treating PCOS on fertility for people with insulin resistance What is Zone2 for a 66 year old Male on a low-carb or ketogenic diet How long did it take you to lose weight on the Plant Paradox' for people with insulin resistance 📗 The 30-Week Tirzepatide Reset — Get Russell's complete protocol → How often can I eat in season fruits — how a functional medicine approach differs Zone 2 at 180 BPM… Lactate test shows max HR 207 — anyone else in this boat and the role of cortisol and stress hormones Does the estradiol gel-associated bloating subside? Smoking while on glp1 📖 Tirzepatide Micro-Dosing — The practice of using the lowest effective dose to achieve results, minimizing side effects while maximizing the longevi… Best recipe book for those with hypothyroidism or Hashimoto's How much fruit, chocolate, or dairy is too much: what to track and how to measure progress