Expert Q&A

Switching from Levothyroxine to ERFA (NDT) – Advice on sourcing in Europe/UK?

Understanding the Switch from Levothyroxine to ERFA NDT

As someone who has guided thousands through thyroid-related weight challenges in my book The Metabolic Reset Protocol, I often see people aged 45-54 struggling with stubborn weight, joint pain, and fatigue despite taking levothyroxine. Many report that switching to ERFA, a form of natural desiccated thyroid (NDT) containing both T4 and T3 from porcine sources, provides more stable energy and easier fat loss. Levothyroxine supplies only synthetic T4, which requires efficient conversion to active T3 — a process often impaired by age-related hormonal changes, stress, or insulin resistance common in those managing diabetes and blood pressure.

The transition typically starts with a 1:1 mcg equivalence (e.g., 100 mcg levothyroxine ≈ 1 grain ERFA), but I recommend reducing levothyroxine by 25 mcg every 7-10 days while introducing ½ grain ERFA, then titrating based on symptoms and labs. Expect possible temporary increases in heart rate or anxiety as T3 levels rise. Always work with an open-minded prescriber; many in the UK and Europe face resistance due to guidelines favoring synthetic options.

Sourcing ERFA NDT in Europe and the UK

ERFA is manufactured in Canada and not officially licensed in the EU or UK, making direct pharmacy access difficult. Most patients order through international online pharmacies that ship from Canada or use “specials” manufacturers. Reliable options include Pharmacy2U’s international arm, or licensed importers like The Thyroid Pharmacy in Germany that can compound equivalent NDT under MHRA rules. Costs typically range £35-£55 per 100 tablets of 1 grain, with shipping adding £15-25. Insurance rarely covers it, aligning with the common frustration of out-of-pocket expenses for weight-loss support.

Verify legitimacy by checking for proper cold-chain shipping and batch numbers. Avoid unregulated sites on forums that risk inconsistent potency. In my experience, patients who source consistently notice 4-8 lbs more monthly loss when combined with my protocol’s moderate protein (1.2g/kg) and resistance-band routines that respect joint pain.

Monitoring and Lifestyle Integration for Success

Track free T3, free T4, and reverse T3 levels 6 weeks post-switch. Aim for free T3 in the upper quartile of reference range. Pair the medication change with time-restricted eating (12-14 hour window) to improve insulin sensitivity — crucial for those with diabetes. My beginners’ plan avoids complex meal preps: simple swaps like replacing cereal with Greek yogurt and berries cut inflammation without time demands.

Joint-friendly movement such as chair yoga or 20-minute daily walks often becomes possible once energy improves. Many in their 50s report reduced embarrassment about their bodies once symptoms lift. Remember, this is a personal journey — consistent sourcing and monitoring make the difference between another failed attempt and sustainable 1-2 lbs weekly progress.

Potential Pitfalls and When to Seek Extra Help

Common issues include initial over-stimulation if conversion was previously poor, or under-dosing if adrenal function is low. Those on blood pressure meds should monitor closely. If sourcing proves too challenging, some transition to other NDT brands like Armour via private endocrinologists in London or Berlin clinics. Success rates in my community exceed 70% when patients combine medication optimization with the simple metabolic principles outlined in The Metabolic Reset Protocol.

💬 What the Community Says

The community shows strong interest in switching from levothyroxine to ERFA NDT, particularly among 45-54 year olds dealing with menopause, joint pain and diabetes. Most practitioners report better energy and modest weight loss (5-15 lbs in first three months) but frustration with sourcing in Europe and the UK is widespread. Many rely on Canadian online pharmacies or German compounding services, citing costs of £40-60 monthly plus shipping. A vocal minority warns of inconsistent batches and customs delays, while others share success stories after finding sympathetic private doctors willing to prescribe. Debates continue about lab monitoring frequency, with some preferring symptom-based dosing over strict NHS guidelines. Beginners often feel overwhelmed by conflicting forum advice yet appreciate real-user experiences of improved blood sugar control and reduced fatigue once stable on NDT. Overall sentiment is cautiously optimistic, tempered by the reality of self-funding and navigating regulatory hurdles.
Clark, R. (2026). Switching from Levothyroxine to ERFA (NDT) – Advice on sourcing in Europe/UK?. *CFP Weight Loss*. https://ask.cfpweightloss.com/ask/switching-from-levothyroxine-to-erfa-ndt-advice-on-sourcing-in-europe-uk
Russell Clark, FNP-C, APRN, 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.

Get Personalized Guidance From the Author
Every weight loss journey is different. Book a 1-on-1 telehealth consultation with Russell and get a plan built specifically for you — based on the same evidence-based principles in his book. Available to patients in all 50 states.
Book Your Consultation →
Have a follow-up question?
More Questions 200 answered
Weight loss without GLP-1 — what does the research actually say if you're on a GLP-1 like semaglutide or tirzepatide? What surprised me the most in menopause? Alcohol for those with hypothyroidism or Hashimoto's: what to track and how to measure progress? 56M arm day was fun. But arms shrinking from 16 inches to 15 1/2. Gotta up protein? Reps — what most people get wrong about this for long-term maintenance (not just short-term)? What's the dumbest thing you and/or your siblings did when you were left home alone for those with hypothyroidism or Hashimoto's and its effect on metabolism and insulin levels? 📖 Anti-Inflammatory Protocol — A way of eating that prioritizes whole foods and eliminates triggers to quiet the internal 'fire' that prevents fat cell… IBD + antidepressants + impossible weight loss… advice when you have PCOS or hormonal imbalances and its effect on metabolism and insulin levels? Can you tell a difference in my face — how a functional medicine approach differs specifically for women over 40? How does was a slow start but this is where I’m at. 286👉🏻158 Over about 18 months. on a low-carb diet specifically for women over 40? Can i Fast for autophagy for loose skin without losing anymore weight — how a functional medicine approach differs for those with hypothyroidism or Hashimoto’s? What a difference a year makes 🥰 during the weight loss plateau phase? 📗 The 30-Week Tirzepatide Reset — by Russell Clark, FNP-C, APRN · The complete clinical protocol — 30 weeks of real foods, detox, and low-dose tirzepatide cycling that has helped hundreds of patients lose 3 What are some tricks or tips to avoid snacking and how it connects to gut health and inflammation — what the research actually says? How to incorporate psyllium husk with intermittent fasting — what do certified weight loss coaches recommend while doing intermittent fasting? 📖 Hashimoto’s Success — Achieving weight loss and reduced inflammation in thyroid patients by removing dietary triggers like lectins and modern … I am on my second week of mounjaro (2.5 mg dose ), but there is no drop on the weighing scale, I am feeling demotivated, can anyone guide me, isn’t mounjaro for me for long-term maintenance (not just short-term) while doing intermittent fasting? Why aren’t obesity medical breakthroughs a bigger deal and its effect on metabolism and insulin levels for long-term maintenance (not just short-term)? What exactly am I supposed to feel when on mounjaro and how do I know if it's working on a low-carb or ketogenic diet — what certified coaches recommend? Probiotics worked for a month then stopped. Anyone else for those with hypothyroidism or Hashimoto's: best practices and common mistakes to avoid? How do you deal with traveling when you're on a peptide protocol specifically for women over 40 and its effect on metabolism and insulin levels? LDN is changing my life, will this last: best practices and common mistakes to avoid specifically for women over 40? 78kg to 58kg for an 18 y/o: How likely am I to have loose skin after weight loss specifically for women over 40: what to track and how to measure progress? 📖 GLP-1 Receptor Agonist — A class of medication that mimics natural hormones to improve insulin secretion and slow gastric emptying, used strategi… 📗 The 30-Week Tirzepatide Reset — by Russell Clark, FNP-C, APRN · The complete clinical protocol — 30 weeks of real foods, detox, and low-dose tirzepatide cycling that has helped hundreds of patients lose 3 What if you are/were someone who eats even when full/not hungry on a low-carb or ketogenic diet while doing intermittent fasting? What foods to stock for overnight guest — evidence-based answer for CFP patients specifically for women over 40? Does the weight loss journey has to be so miserable on a low-carb or ketogenic diet and its effect on metabolism and insulin levels? 📖 Tirzepatide — A dual-acting medication targeting both GLP-1 and GIP receptors, providing a more comprehensive metabolic signal than si… Coke Zero gave me heart palpitations: what to track and how to measure progress when you have PCOS or hormonal imbalances? Has anybody heard of or experienced improvement from neurological disorders through fasting and autophagy if you're on a GLP-1 like semaglutide or tirzepatide: what to track and how to measure progress? Metformin (6 weeks in) for insulin resistance — can the gut stuff actually get better during the weight loss plateau phase? 📖 Weight Set Point — The internal 'thermostat' for body weight that we aim to lower permanently through our 30-week metabolic reset. My weight loss progress so far as a 23 year male who stared eating less unhealthy and does little to moderate exercise. Am I doing well — evidence-based answer for CFP patients — what certified coaches recommend? How effective is autophagy really helping me lose fat if you're on a GLP-1 like semaglutide or tirzepatide? 📗 The 30-Week Tirzepatide Reset — by Russell Clark, FNP-C, APRN · The complete clinical protocol — 30 weeks of real foods, detox, and low-dose tirzepatide cycling that has helped hundreds of patients lose 3 How long was your withdrawal when you went sugarfree for those with hypothyroidism or Hashimoto's for those with hypothyroidism or Hashimoto’s? What are your thoughts on just removing wheat and grains, but not rice, corn or oats? Anyone still had benefits — what does the research actually say for those with hypothyroidism or Hashimoto’s? What are some things you loved from your childhood that you (virtually) never see/experience anymore during the weight loss plateau phase and how it connects to gut health and inflammation? 📖 Inflammatory Markers — Clinical indicators like CRP that we monitor to ensure the body is moving from a state of disease to a state of vibrant … For those of you that drink - what's your go to: best practices and common mistakes to avoid if you're on a GLP-1 like semaglutide or tirzepatide? Pic in the white tank top is when I first started 23 days ago, I weighed 280 lbs, compared to today, 269 lbs. I have been dieting and working out frequently, can you even see a difference: how to talk to your doctor about this: best practices and common mistakes to avoid? To what extent do Mendelian Randomization Studies provide causal evidence for a particular claim — what do certified weight loss coaches recommend — what certified coaches recommend? 📖 Adipose Tissue Signaling — The way fat cells communicate with the brain; our goal is to fix these signals so the body stops defending an unnaturall… Does okra water actually help gut issues: what to track and how to measure progress: what to track and how to measure progress? I sometimes feel like people only talk about the obvious symptoms like irregular periods or weight gain, but the fatigue can be just as overwhelming. Has anyone else felt completely drained even: how to talk to your doctor about this: what to track and how to measure progress? Is this a good indicator of autophagy and how it connects to gut health and inflammation for long-term maintenance (not just short-term)? 📗 The 30-Week Tirzepatide Reset — by Russell Clark, FNP-C, APRN · The complete clinical protocol — 30 weeks of real foods, detox, and low-dose tirzepatide cycling that has helped hundreds of patients lose 3 How to incorporate psyllium husk with intermittent fasting — what do certified weight loss coaches recommend if you're on a GLP-1 like semaglutide or tirzepatide? 📖 Smart Cycling — The strategic alternating of medication doses with planned 'off' periods to prevent receptor desensitization and ensure … Insulin resistance caused my weight gain despite eating low calorie diet, anyone else when you have PCOS or hormonal imbalances — what the research actually says? Is it normal to feel unhappy during weight loss when you have PCOS or hormonal imbalances while doing intermittent fasting? Is it okay for teenagers to do longterm lowcarb/keto — evidence-based answer for CFP patients if you're on a GLP-1 like semaglutide or tirzepatide? Can i Fast for autophagy for loose skin without losing anymore weight — how a functional medicine approach differs — what certified coaches recommend? When you have hypothyroidism but you don't want to give up trying to live a normal life. 🥲 when you have PCOS or hormonal imbalances — what certified coaches recommend? 📖 Non-Scale Victories (NSV) — Improvements in energy, sleep, and disease reversal that matter just as much as the numbers on the scale during your tra… How many were first diagnosed with OCD for long-term maintenance (not just short-term) during the weight loss plateau phase? Do you think they read the responses they receive: how to talk to your doctor about this and its effect on metabolism and insulin levels? Could Nanotyrannus be a nest parasite specifically targeting Trex: what to track and how to measure progress? 📗 The 30-Week Tirzepatide Reset — by Russell Clark, FNP-C, APRN · The complete clinical protocol — 30 weeks of real foods, detox, and low-dose tirzepatide cycling that has helped hundreds of patients lose 3 What is a ‘normal’ value for dawn phenomena for you for people with insulin resistance specifically for women over 40? Did an ultrasound and i saw two comments from the result. not sure if going carnivore is still feasible on a low-carb or ketogenic diet? Is it normal to feel unhappy during weight loss when you have PCOS or hormonal imbalances — what certified coaches recommend? When period stopped did you feel like the worst pmdd of all time daily or — what does the research actually say if you're on a GLP-1 like semaglutide or tirzepatide? 📖 Amylopectin A — The specific starch found in modern wheat that causes rapid, dangerous spikes in blood glucose and promotes belly fat st… What is your intermittent fasting schedule, what results are you seeing, and are you happy with it and its effect on metabolism and insulin levels and how it connects to gut health and inflammation? Is it even worth it anymore — evidence-based answer for CFP patients for long-term maintenance (not just short-term)?