Liothyronine (T3) is the most powerful thyroid medication available because it does not need to be activated by your body, peaks quickly, and provides the biggest improvement in symptoms at the lowest dose.
The most commonly prescribed thyroid medication, levothyroxine, only resolves symptoms in about 40% of patients because it is loaded with fillers and must be converted before your body can use it.
Armour Thyroid provides a full spectrum of thyroid hormones including T4, T3, T2, and T1, but its fixed dosing ratio does not work for every patient and it currently faces a potential FDA ban.
T2 is the only thyroid hormone available over the counter and works as a complementary hormone that boosts metabolism, fat burning, and muscle function alongside your other thyroid medications.
If your current thyroid medication is not working, switching to a cleaner formulation like Tirosint or adding T3 to your regimen can make a significant difference in how you feel.

I ranked every thyroid medication from best to worst, and I’m sharing it all with you today.

Most thyroid patients have no idea that the most commonly used thyroid medication is also the worst, or that they have other, better options.

If you are struggling with low thyroid symptoms like weight gain, fatigue, and hair loss, even while taking thyroid meds, this one is for you.

Let’s start with the best:

#1. Liothyronine (S Tier)

This is S tier.

Liothyronine is the strongest and most powerful thyroid medication on the market, by far.

Nothing else comes close to its raw strength and power.

Why is it so effective? For 3 reasons:

The first is that it comes in an immediate-release form.

Both liothyronine and the brand-name Cytomel peak in your bloodstream about 3-4 hours after you take it.

Second: it doesn’t need to be activated.

Unlike T-4 only thyroid meds like levothyroxine, liothyronine is immediately available to your cells right when you take it.

And third: it gives the biggest improvement to thyroid symptoms at the lowest dose.

Thyroid patients who add liothyronine see the fastest drops in weight loss and the biggest gain in energy.

The biggest con for this medication is that it’s hard to get.

And doctors who do prescribe it tend to underdose it because of its strength.

But if you can find a doctor who is willing to give it to you at the doses you need, you will feel amazing.

#2. Sustained Release T3 (S Tier)

This is still technically S-tier, but it’s low S-tier.

Sustained-release T3, known as SR T3, is not quite as good as liothyronine, but it’s still a phenomenal thyroid med.

The main difference between these two is in how quickly they get absorbed into your system.

This form comes bound to compounds that delay its release in the GI tract.

The result is a more stable and balanced absorption throughout the day.

Why would you even want this?

Well, that has to do with the power of T3.

Because T3 is so strong, it can cause symptoms like jitters, anxiety, and heart palpitations, which are troubling for thyroid patients.

Using SR T3 over IR T3 can eliminate these symptoms while allowing you to maintain all of the benefits of pure T3, like not having to worry about the conversion process.

There is one major con to using this med, and that is its absorption.

Sometimes the compound that it is bound to works too well, and your body is unable to break it apart and absorb the T3.

This is especially common in thyroid patients with gut problems.

It’s great if you are sensitive to IR T3, but it won’t work for everyone.

#3. Armour Thyroid (A Tier)

I’m calling this the top of A tier.

Armour thyroid is, by far, the best “natural” option out there.

In the class of medications known as natural desiccated thyroid, this med comes with a full spectrum of thyroid hormones including T4, T3, T2, and T1.

Taking it also gives you some additional goodies like calcitonin and minerals.

Some people are probably going to get upset at me for putting this in the A-tier list, but let me explain why:

these work when levothyroxine doesn't shop now

Even though Armour is a good medication, it’s not the best for a few reasons:

First is that its dosing is static. Each grain comes with a standardized amount of T4 and T3.

This is great if the ratio it comes in happens to work for you, but bad if it doesn’t.

And spoiler alert, most thyroid patients need individual titration of their T4 and T3 hormones.

Second is that it’s difficult to get from your doctor.

You’ll probably have an easier time getting liothyronine than you will Armour thyroid.

And third is that it’s currently at risk of being banned by the FDA.

Armour has a target on its back right now. And while I’m not convinced that it will get banned, there’s still a small possibility.

And nothing would be worse than optimizing a brand-new thyroid med, only to have it be taken away.

So for these reasons, I’m putting it in the A tier.

#4. T2 (A Tier)

Yes, I know, T2 is not technically a medication, but it is a thyroid hormone, so I’m including it here.

T2, also known as 3,5-diiodo-l-thyronine, is the only thyroid hormone available over the counter.

In terms of raw power, it’s not as strong as T3 meds or Armour thyroid, but it still has several benefits that make it incredibly useful:

We already mentioned the fact that it’s available over the counter, which can’t be overstated.

In a world where all of the best thyroid meds are gated behind a prescription pad, it’s great to have an option that you are 100% in control of.

On top of this, T2 is an active thyroid hormone on its own.

Unlike levothyroxine, T2 doesn’t need to be activated for your body to use it.

From the first dose you take, you will start to get benefits on metabolism, fat burning, liver health, and muscle function.

And finally, it’s usable with all other thyroid meds.

Instead of thinking about T2 as a “this instead” thyroid hormone, think of it as a complementary hormone that makes everything else work better.

Its biggest con is the fact that it’s not covered by insurance.

As far as pricing goes, it’s more expensive than levothyroxine but less expensive than Armour.

#5. Tirosint & Tirosint Sol (B Tier)

These are solid B-tier. Why B?

As far as T-4 only thyroid medications go, they are the best and the cleanest.

But they are still T4-only thyroid meds, which means they aren’t active on their own.

The fact that they are so clean does count for something, though.

Both Tirosint and Tirosint-sol have the fewest binders of any other thyroid medication, Cytomel and liothyronine included.

Fewer inactive ingredients, binders, and dyes mean a smaller chance that your body will react to each dose.

And we know from research that even small doses of certain fillers can limit the effectiveness of a thyroid medication.

The classic example is the lactose found in Synthroid.

This small amount of lactose is enough to reduce its absorption, leading to persistent thyroid symptoms.

Most thyroid patients who switch from levothyroxine to Tirosint, even at the same dose, see better symptom control.

The biggest con of these medications is that you won’t feel 100% better unless you add T3 and T2.

#6. Levothyroxine (C Tier)

Levothyroxine is solid C tier, putting it lowest on the list.

If I’m being totally fair, it’s really not as bad as most people think.

You’ll hear that it doesn’t work because it’s synthetic, but that’s actually not the problem with it.

The problem is that it’s loaded with fillers and dyes, and that it needs to be converted before your body can use it.

In addition, it’s prescribed something like 80 million times per year. And based purely on statistics, it only resolves symptoms in 40% of thyroid patients.

That means there are millions of thyroid patients out there using it who still feel terrible.

Does the fact that it’s synthetic play a role? Not as much as you’d think.

If we are strictly looking at the molecular structure of levothyroxine, it’s identical to the T4 found in Armour thyroid.

The big difference is the source, and that armour has other thyroid hormones that come along with it.

Even though my favorite thyroid medication is liothyronine, I would still recommend and use levothyroxine from time to time.

So don’t worry about it if it’s working for you.

But If you are one of the 60% that has issues with it, don’t hesitate to swap it.

The Cheat Sheet

Save this for your next doctor’s visit:

#1. Liothyronine (Immediate weight loss + energy)
#2. SR T3 (Smooth symptom control)
#3. Armour (Natural & balanced option)
#4. T2 (OTC metabolism booster)
#5. Tirosint & Tirosint-sol (Clean T4 / Gut friendly)
#6. Levothyroxine (Standard but weakest)

Here’s the bottom line:

You don’t need to be taking an S-tier thyroid med to feel better.

Will taking one give you a better shot at feeling better? Of course.

But feeling better is more about finding what works for you.

And even if you are someone who must take a T4-only medication like levothyroxine, there are still things you can do to make it work more effectively.

Check out this article next if you want to see what I’m talking about.