Mounjaro fatigue

Also, all my blood work and tests—-thyroid, testosterone, cortisol, ACTH, kidney ultrasound, eGFR have come back normal. A1c 6.3

I am the same age, taking the same meds, and feel like the walking dead.
I have decided to take the holistic route in order enjoy some realistic venues of life.
Taking several medications for various ailments create severe complications. At our age, we should seek balance
utilizing common sense, and paying close attention to what our bodies are telling us. For me life has been
fulfilling, and, I am finding diet, exercise, and natural herbs a beautiful alternative to uncharted medicine.

I am not a doctor or anything.
The fact that his thyroid, testosterone, cortisol, ACTH, and kidney function tests are all normal is excellent. It rules out the most common endocrine and renal causes of fatigue. However, this makes the fatigue a more urgent signal, not a less urgent one.

1. Cardiovascular Issues (Highest Concern)
For an older male with diabetes, severe, debilitating fatigue and a new inability to handle exertion can be a "red flag" for a heart problem. This symptom, when it replaces traditional chest pain, is known as an "anginal equivalent."

Why it's a concern: Diabetes can damage the nerves that would normally send a "chest pain" signal to the brain. Instead, the signal of heart distress (ischemia, or lack of oxygen) is expressed as profound fatigue, shortness of breath, or weakness.
What this means:His fatigue could be a sign of a blocked artery or worsening heart failure. This must be the first thing to rule out.

2. Hypoglycemia Unawareness (High Possibility)
Randy's A1c of 6.3 is outstanding, but because he takes insulin, it may be *too* tight. An A1c this low suggests he might be having episodes of low blood sugar (hypoglycemia) that he is no longer feeling.
Why it's a concern: After many years of diabetes, or in older adults, the body can stop giving the usual warning signs of a low (shaking, sweating, anxiety). This is "hypoglycemia unawareness."
What this means: He could be experiencing lows, especially at night, and the "symptom" he feels hours later is the debilitating fatigue and "washout" feeling. The body is exhausted from the event. He should check his blood sugar immediately when he feels this fatigue.

3. Medication Side Effects (Still Possible)
You are correct to question the medications, though the order of suspicion may be different.
Mounjaro (Tirzepatide): As you noted, it takes about a month for it to clear the system. Since the fatigue has not improved, Mounjaro is *unlikely* to be the primary cause.
Pravastatin (Statin): It is *possible* for statin-induced muscle fatigue (myopathy) to appear after long-term use, though it is less common than it appearing early. Research suggests this side effect is more common in women, which makes it a slightly less likely (but not impossible) cause for Randy.

His situation has moved beyond simple side effects. He needs to see his doctor immediately to report that the fatigue persists despite stopping Mounjaro. The doctor needs to investigate two urgent possibilities:

1. A full cardiac workup(like a stress test or echocardiogram) to rule out heart disease.
2. A review of his blood sugar logs to check for hypoglycemia. He may need to raise his A1c target (e.g., to 7.0-7.5%) by reducing his insulin to be safer.
3. A simple blood test (a CBC) to check for anemia, which was not on your list of normal tests and is a very common cause of fatigue.

Some very interesting replies above.

I am a 74 YO male. I have been fatigued for the last 4 years. And no one really could tell me why or how to cure it. I have stopped taken certain meds to see if they are the cause but they were not.

I finally went to an endocrinologist since I had all the symptoms of Addison's disease. One big side effect was chronic fatigue. I just started taking the med for Addison's. So I shall see if that will help my fatigue.