Levothyroxine Sodium Oral Solution Normalizes Thyroid Function in a Patient with Hashimoto’s Disease, Gastritis, Diabetic Gastroparesis, and Small Intestinal Bacterial Overgrowth (SIBO)

Figures & data

Table 1 Thyroid Timeline Before Administration of L-T4 Oral Solution

Treatment/Action Taken/Presentation	Initial Presentation	6 Weeks	12 Weeks	18 Weeks	24 Weeks
	L-T4 Tablet (Synthroid^®) 125 µg	T4/T3 Compounded Medication	T4/T3 Compound at Escalated Dosing	T4/T3 Compound at Escalated Dosing	Started with Worsening GI Issues, Gastroparesis, and Vomiting
TSH, mIU/L (NR 0.45–4.50 mIU/L)	5.30	4.65	6.50	2.60	7.42
Free T4, pmol/L (NR 10.55–22.78 pmol/L)	16.60	16.60	18.53	24.07	19.82
Free T3 pmol/L (NR 3.39–6.16 pmol/L)	Not evaluated	4.47	5.24	4.93	5.24

Abbreviations: GI, gastrointestinal; L-T4, levothyroxine; NR, normal range; T3, triiodothyronine; T4, thyroxine; TSH, thyroid-stimulating hormone.

Figure 1 Thyroid-stimulating hormone timeline.

Abbreviations: L-T4, levothyroxine; T3, triiodothyronine; T4, thyroxine; TSH, thyroid-stimulating hormone.

Table 2 Thyroid Timeline After Administration of L-T4 Oral Solution

Treatment/Action Taken	24 Weeks	30 Weeks		36 Weeks		42 Weeks
		L-T4 Oral Solution 150 µg		L-T4 Oral Solution 150 µg		L-T4 Oral Solution 112 µg
TSH, mIU/L (NR 0.45–4.50 mIU/L)	Switched to L-T4 oral solution 150 µg	1.55	1 treatment cycle of rifaximin for SIBO	0.56	L-T4 oral solution down-titrated to 112 µg	1.95
Free T4, pmol/L (NR 10.55–22.78 pmol/L)		27.93		29.99		20.33
Free T3, pmol/L (NR 3.39–6.16 pmol/L)		4.93		5.39		4.77

Abbreviations: L-T4, levothyroxine; NR, normal range; SIBO, small intestinal bacterial overgrowth; T3, triiodothyronine; T4, thyroxine; TSH, thyroid-stimulating hormone.