Phase 4: T3 Thyroid Therapy (Rebooting Your Metabolism)

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Where T3 can actually hurt you

T3 raises your heart rate and metabolic demand. At the doses described here it is real medicine with real force behind it. These are the cases where you slow down and build the prep first, and a couple where you get my eyes on your numbers before you touch it.

A heart rhythm problem or heart diseaseArrhythmia, atrial fibrillation, or known heart disease. T3 can push an unstable heart into dangerous territory. This is one to run past me with your own numbers before you start.
Known osteoporosis or low bone densityLong-term, high-dose T3 can accelerate bone loss. Load the K2 and bone-support stack (below) before you climb.
On anticoagulants such as warfarinT3 changes how these drugs behave, so the anticoagulant dose usually needs to come down as thyroid comes up. Get this dialed in before you start, not mid-climb.
Pregnant, or a history of thyrotoxicosisThese are the two here where you want real oversight before any thyroid hormone. Worth running past me first.
Resting heart rate already above 90 bpmResolve that first. An elevated resting heart rate is a contraindication to starting T3.

Many people with chronic illness are stuck in a state where their body is “hibernating” to save energy. Even if your blood tests look normal, your body might not be using thyroid hormones correctly. This phase uses a hormone called T3 to “reboot” your body’s thermostat and turn your energy back on.

Is This Therapy Right for You?

Main Requirements (You must have these)

1. Low Waking Temperature:Is your temperature consistently below 36.5°C (97.7°F) first thing in the morning? This is the main sign your metabolism is slow.
2. Low Heart Rate:Is your resting heart rate below 72 beats per minute? This also suggests a slow metabolism.
Note: If your resting heart rate is above 90 bpm, resolve that first. An elevated resting HR is a contraindication for starting T3 therapy.

Other Common Symptoms

(Check how many you have – the more you have, the more likely you need this)

Quick Check:

Low Morning Temp + Low Pulse + 3 or more symptoms → You may be a good candidate for T3 therapy.

Track your temp and pulse for one week to be sure.

Getting an Accurate Temperature Reading

Use a Basal Body Thermometer, Not a Standard One

Your waking temperature is one of the most important data points in this entire protocol. A cheap drugstore thermometer that reads to one decimal place is not good enough. You need a thermometer precise enough to detect meaningful shifts, the kind used for tracking fertility windows.

Digital basal body temperature thermometer for precise tracking

A digital basal body thermometer that reads to two decimal places and holds the result for easy reading

What to Use:A digital basal body thermometer, the kind sold for fertility tracking (ovulation monitoring). These read to two decimal places (e.g., 36.48°C rather than 36.5°C), which gives you the precision needed to track real trends over days and weeks. They are inexpensive and widely available online or at pharmacies.
How to Take It Correctly:Place the thermometer under the tongue and hold it there for at least 60 seconds before the reading locks. Most standard thermometers beep too early. A basal thermometer is designed to wait for a true stable reading. Take it before getting out of bed, before drinking anything, and at roughly the same time each morning. Movement, eating, and even sitting up will raise your temperature and give you a false reading.
What You Are Looking For:Log your temperature every morning. You are tracking a trend, not a single number. As T3 therapy works, you should see your waking temperature gradually climb toward 36.5 to 37.0°C (97.7 to 98.6°F) and stabilize there. Erratic readings, persistent sub-36°C temperatures, or a temperature that rises but then drops again are all meaningful signals worth noting.

Introduction to T3 Therapy

Overview: This therapy uses T3 (thyroid hormone) to help with fatigue and low body temperature. The goal is to “restart” your metabolism. You can dive deeper into it on this site: wilsonssyndrome.com

Wilson’s T3 Therapy & Dry Fasting for Chronic Illness: a detailed breakdown of why this combination works when nothing else has.

The Best Way: Slow-Release T3 (SR-T3)

I strongly recommend using Slow-Release T3 (SR-T3).

Where to Get T3

One trusted source for Slow-Release T3 is chronic-illness.st. They specialize in this medication and can ship to many places. (Previously chronic-illness.ca, the site has recently migrated.)

If you have trouble getting your medication, I can help you find a way to get what you need.

Why Your Blood Tests Might Lie to You

The Real Problem: Tissue-Level Resistance

Most doctors look at your blood to see if you have enough T3. But just because T3 is in your blood doesn’t mean it’s getting inside your cells where it’s needed. This is called tissue-level resistance.

Side-by-side: the same lab result, two completely different cellular realities. This is why “your labs are normal” is not the answer chronic illness patients need.

Think of T3 as a “key” and your cells as “doors.” In many sick people, the locks are jammed. The T3 keys are floating around in the hallway (your blood), but they can’t get into the rooms (your cells) to turn on the power. When a doctor draws your blood, they see plenty of keys and say, “You’re fine!” Even though your body is actually starving for energy.

Brain Insulin Resistance

This problem is especially serious in the brain. When T3 can’t get into your brain cells correctly, it leads to a type of “brain insulin resistance.” This causes major brain fog, memory problems, and severe fatigue. Even if you eat enough food, your brain can’t use that energy properly without the T3 “key” to unlock the process.

Other Signs of Resistance:

T3 therapy is used to “electrify” the body, sending a structured “electrical signal flood” of abundance and shock to finally force those jammed locks open and wake your body up. This convinces the cells that T3 can enter again and radically increases insulin sensitivity. Depending on the case, this may require a mix of T4 and high T3, or just T3, but the concept of a short, powerful energy burst remains the same. Do not forget to understand the critical co-factors required for T3 therapy to be safe and effective.

The Role of Genetics: In some cases, your genetics can play a big role in how your body handles T3. Fasting, stress, and low-carb can have different effects on different people. To learn more about this, visit the Genetic Polymorphisms page.

When to Start T3: After the First 7 Days of Refeeding

Finish the Fast First. T3 Starts After 7 Days of Refeeding.

In the Scorch Protocol, T3 does not run during the fast. You finish the whole fast, the dry fast first and then the water fast, with no T3 on board. The fast is doing its own work: clearing damaged cells, draining the viral reservoir, resetting insulin signaling. Loading a metabolic accelerant on top of that while zero calories are coming in is how you burn muscle and stress the heart for nothing. Let the fast finish clean.

What you do carry straight through the fast-to-refeed transition is your viral reactivation protocol. L-lysine comes back on water day 1 and monolaurin and olive leaf come in with the first meal, holding the natural line. Valacyclovir joins as the standing antiviral backbone on refeed day 3 at the earliest (never during the fast, dry or water, since a water fast still leaves the body dehydrated and the drug is renally cleared), with ivermectin alongside it as supportive coverage plus the primary antiparasitic, and a valacyclovir loading dose layered on top if you feel a prodrome coming on once the course is running. None of it pauses once the standing course is running. That handoff from fasting to eating is the exact energetic trough where dormant herpesviruses wake up, so the antivirals stay on through the transition and across the entire refeed. Do not drop them the moment you start eating.

The First 7 Days of Refeeding: Rebuild the Engine Before You Rev ItDuring the first 7 days of refeeding, before any T3, the job is mitochondrial and metabolic support. This is where methylene blue comes in, and in some cases ethyl pyruvate as well. Coming out of a fast, the cell is carrying a heavy load of NADH from all that fat-burning, a kind of reductive stress, and if the electron transport chain cannot clear it that NADH backs up and stalls energy production. Methylene blue fixes the electron redox directly: it acts as an alternative electron carrier, accepting electrons from the backed-up NADH and passing them down the chain, restoring the NAD+ to NADH balance so the mitochondria can make energy again. These are decided case by case with each individual. There is no dose printed here, and that is deliberate: methylene blue and ethyl pyruvate are individualized in your consult, matched to your own presentation, never a generic number pulled off a webpage.
Then T3 Starts: After Day 7 of the RefeedOnce you have 7 days of refeeding behind you, with fuel flowing and the mitochondria supported, T3 begins. From there the 30-day cycle below runs exactly as written: the 15 mcg/day climb, the short hold at the peak, and the slow 20-day taper. Starting T3 after the refeed is established, instead of mid-fast, means you never ask a metabolic accelerant to run on an empty tank. The calories are already there, the antivirals have held the line, and the mitochondrial support has done its prep work.
Adjust for Body Composition:The 7-day mark is the floor, not a fixed date. It assumes you are carrying enough body fat to fuel what T3 demands. If you are very lean or close to skin-and-bones, starting T3 even after 7 days can trigger an adrenaline surge, so keep refeeding and rebuilding further before you begin. When you are unsure how much refeed runway you need, this is a timing call worth confirming with me directly.
The Taper Is Also a High-Risk Window for Viral Reactivation:When a T3 cycle ends and the dose tapers down, your metabolic rate temporarily dips. That dip is the same energetic trough that lets herpesviruses flare during the fast-to-refeed transition. Keep antiviral coverage running through the T3 wind-down until your waking temperature has held at your baseline for 5 to 7 consecutive days.

The 30-Day T3 Cycle

This plan is designed to wake up your body’s metabolism. It involves a 10-day “climb” followed by a 20-day “descend.”

PhaseTimeWhat to Do
The Climb10 DaysThe Hike Up: Increase your total daily dose by about 15 mcg every single day.
Example: Day 1 = 15mcg, Day 2 = 30mcg, Day 3 = 45mcg...
Note: Split your total dose into two parts: one in the morning and one in the evening.
The Peak1–3 DaysStay at your highest dose for a few days to “break” your metabolism’s resistance. If your heart races or you feel anxious, stop increasing.
The Taper20 DaysThe Hike Down: Slowly lower your dose back to zero.
This lets your thyroid start making its own hormones again without a crash.
Simplified T3 Protocol Chart

Figure 1: Simplified T3 Protocol Dosing & Tracking Chart

Safety First

Is your heart racing?If your resting heart rate is over 100 beats per minute, → STOP INCREASING. Stay at your current dose or lower it until your heart rate slows down.
Are you using “Instant” T3?→ WARNING: This fast 10-day climb is only for Slow-Release T3. Do not try this with regular “instant” T3 unless you are very careful and take many small doses throughout the day.
Having trouble stopping?→ If you feel shaky while lowering your dose, that is usually your T4 running out. Near-zero TSH means your own T4 is gone, so nothing is buffering the dropping T3. The fix is to add a little T4 back on top of the T3 you are still lowering: 50 to 100 mcg of T4 every other day. T4 has a long half-life, so every-other-day dosing holds a steady floor (slow-release T4 is available from chronic-illness.st or other sources). Desiccated thyroid (30 to 60 mg) is the accessible fallback if you cannot get a formulation. This is the kind of adjustment worth running past me.
On a second cycle and still struggling with energy or the fast itself?→ Some people do better on a custom T4/T3 ratio for the next round. Find your full thyroid replacement rate and run about half of it through the fast. Medical caveat: this is the one per-case exception to the rule that T3 does not run during the fast, never the default.

Drug Interactions You Need to Know About

Thyroid can thin blood, especially at higher doses. Patients on warfarin sodium (Coumadin®) or other anticoagulants may develop an increase in prothrombin time requiring a lowering of their anticoagulant therapy while taking thyroid medication. Drug-drug interactions may occur with other anticoagulants, oral hypoglycemic agents (increased requirements), insulin (increased requirements), estrogens and oral contraceptives (increased thyroid requirement), tricyclic antidepressants (enhanced effects), cardiac glycosides (potential toxicity and reduced dose) and cholestyramine (decreased T3 and T4 absorption). Several drugs, including cimetidine, ranitidine, glucocorticoids, amiodarone and beta-receptor antagonists, have been reported to increase the hepatic metabolism of T4 into reverse T3 by inhibiting 5’-desiodinase, the hepatic microsomal enzyme catalyzing the conversion of T4 into T3.

Keeping Your Progress

The Co-Factor Stack That Makes T3 Stick

T3 reboots metabolism, but whether it holds depends on three things going right at the same time: you have to eat enough, you have to sleep, and your stress hormones have to come down instead of spiking. The protocol uses a small co-factor stack to protect all three.

Cyproheptadine (appetite, sleep, stress, mitochondria):Its main job in the first T3 cycle is to drive you to eat dramatically more food so you fill the wider metabolic eating window T3 opens. Without sufficient calories T3 burns muscle, not fat. Cyproheptadine fixes that by restoring the appetite T3 demands. It also calms a hypersensitive, nauseated gut by quieting the brain-gut nerves (the same mechanism behind its well-established use for cyclic vomiting and abdominal migraine in children), which makes eating much larger amounts tolerable even when the gut is not ready.
Additional effects: cortisol, sleep, and mitochondrial uncouplingIt blunts the serotonin and cortisol surge that T3 can provoke, reducing muscle catabolism and settling the nervous system into the calm state mitochondria need to respond to T3 instead of fighting it. As an anti-serotonin drug it also supports mitochondrial uncoupling: the mitochondria burn fuel to produce heat, which raises body temperature and metabolic rate, directly supporting what T3 is driving. And it is T3-sparing: some patients who barely respond to T3 are tempted to push the dose above the roughly 150 mcg/day Wilson’s protocol ceiling, which carries more cardiac and adrenal risk. Adding cyproheptadine often lets the existing T3 dose reach the target temperature instead, avoiding that escalation. Dose is 1 to 4 mg in the evening, set individually in your consult. See the Symptom Management page for MCAS context and the ketotifen comparison.
Cyproheptadine and hGH work together. You may have read that cyproheptadine has to be stopped before hGH because it lowers growth hormone. That is not the case. Cyproheptadine blunts the pituitary’s own signal to release GH, but the hGH phase injects growth hormone directly, so it bypasses the pituitary entirely and overrides the blunting. The nighttime cortisol point does not change this either: the goal of hGH here is regeneration and calming the nervous system, not overnight fat loss, and the rebuilding actions of hGH stay fully active even with cortisol softened. Cyproheptadine can continue into the hGH cycle wherever appetite, gut tolerance, or sleep still call for it.
Low-dose aspirin (inflammation, cortisol, insulin sensitivity):Lowers the inflammatory drag and peripheral cortisol conversion that keep cells resistant to T3. See the Tips & Tricks aspirin section for dosing and safety.
Vitamin K2 (vascular protection):Non-negotiable alongside aspirin to protect clotting and arterial health, and it supports the bone health T3 therapy demands. Use MK-4 or MK-7.
Vitamin D3 + K2 (immune, bone, mood):The co-factor that pairs best with T3. In my experience most chronically ill patients run deficient, and correcting it steadies immune function, protects bone while T3 is driving hard, and lifts mood. Run D3 together with K2 (the same K2 that partners your aspirin above). If your vitamin D is below 40 ng/mL, dose 5,000 to 10,000 IU/day of D3 through this phase.

None of these replace T3. They are what keep T3 working long enough to reset your baseline.

Ideal body temperature curve throughout the day for a healthy person

Figure 2: The ideal body temperature curve of a healthy person, rising through the day and peaking in the late afternoon. If your T3 therapy works, your temperature pattern should begin to match this curve.

Thermoregulation across five cycles of slow-release T3 therapy in a 51-year-old woman, showing waking temperature climbing from a sub-36°C baseline toward the healthy 36.5 to 37.0°C range

Figure 3: Real-world thermoregulation data across five cycles of slow-release T3 in a 51-year-old woman. Each cycle progressively lifts the waking temperature baseline toward the healthy 36.5 to 37.0°C range shown in Figure 2, the pattern most participants follow when the protocol is working.

Fueling T3 Therapy: Why Calories Matter Here

T3 dramatically increases your metabolic rate. That is the point. But a faster metabolism with insufficient fuel will cannibalize muscle. You must not be in a caloric deficit during this phase.

Match Your Caloric Demand:As T3 doses climb, your body burns more energy. If you are not eating enough to cover that demand, the body will turn to muscle tissue for fuel, the opposite of what you are trying to achieve. Keep calories at or above your target (see the Refeeding page) and prioritize protein to give your body something to build with, not just burn.
Make the Calories Dense: This Is a Must-Do, Not a PreferenceHere is where people quietly fail this phase. T3 throws the eating window wide open, and it is on you to actually fill it. A wrecked appetite cannot hit 3,000-plus calories a day on bulky, watery, low-calorie food: you get full long before you get enough. So make every bite count and go calorie-dense: olive oil and butter on everything, full-fat dairy, eggs, fatty fish and meat, nut butters, honey, white rice, ripe fruit. When high T3 opens the window and you leave it half-filled, the body does not coast, it strips muscle and lean tissue to cover the demand you just created. Covering that window with dense, high-calorie food is the line between rebuilding and wasting away.
Move Your Muscles: Tell Your Brain to Keep ThemPhysical movement during T3 therapy sends a preservation signal. Your body will not aggressively break down muscle tissue it is actively using. You do not need to train hard. Even walking, light resistance work, or bodyweight movements daily is enough to keep the muscle-sparing signal active. Lying still while on T3 with insufficient calories is the worst combination.
When You Cannot Hit High Calories Yet:Some people, especially in the first days of the T3 cycle, cannot physically eat enough to match T3’s demand. Their gut is not ready, appetite is suppressed, or digestion is too compromised. In this case, there are specific strategies that can help:
  • hGH: directly shifts the body toward anabolism and preferential fat use, reducing the rate at which muscle is burned for fuel even when calories are temporarily low.
  • Retatrutide: a GLP-1/GIP/glucagon triple agonist that improves glucose utilization and raises baseline energy availability. The glucagon component is particularly useful for people stuck in low-energy states.
  • Cyproheptadine: the primary first-cycle lever for filling the eating window when appetite is broken or the gut is hypersensitive. It restores the drive to eat, calms the brain-gut nerves that make large meals nauseating, and deepens sleep when repair on T3 happens. For many people this is the single cheapest way to get calories back up early in the refeed. It is introduced in the first cycle, but it does not have to stop when hGH begins: see the cyproheptadine and hGH note.
Important: If you do not understand how hGH or Retatrutide work and why they are recommended in this context, do not use them. These are not general supplements. They are targeted tools with specific mechanisms. Read the hGH Therapy page and understand the protocol before considering them.

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References

  1. Cahill GF Jr. Starvation in Man. New England Journal of Medicine, 1970. — the fasting-metabolism timeline: the brain's shift to ketones and muscle sparing once ketosis is established, and why T3 must be paired with adequate fuel
  2. Influence of absolute (dry) fasting on metabolic processes and organ function. — profound insulin suppression and improved insulin sensitivity (HOMA-IR) during fasting

See the full research & citations page for the complete evidence base and how each study is used.

Further reading from the blog

The information on this site describes a personal health protocol and is provided for educational purposes only. It is not medical advice. Consult a qualified physician before modifying your diet, fasting practice, or any medication regimen.