{"id":628288,"date":"2024-05-17T11:34:24","date_gmt":"2024-05-17T15:34:24","guid":{"rendered":"https:\/\/www.singlecare.com\/blog\/?p=628288"},"modified":"2026-03-24T17:57:10","modified_gmt":"2026-03-24T21:57:10","slug":"tirosint-vs-synthroid","status":"publish","type":"post","link":"https:\/\/www.singlecare.com\/blog\/tirosint-vs-synthroid\/","title":{"rendered":"Tirosint vs. Synthroid: Differences, similarities & side effects"},"content":{"rendered":"

Tirosint and Synthroid are two brand-name medications used to treat <\/span>hypothyroidism<\/span><\/a> (an underactive thyroid) and thyroid cancer. They are classified as thyroid replacement hormones and work by replacing thyroid hormones that are normally produced by the body. Although both medications are known as thyroid hormone replacement medications, they have some differences, as we will discuss below.<\/span><\/p>\n

Tirosint vs. Synthroid: Key differences<\/span><\/h2>\n

Tirosint<\/span><\/a> and <\/span>Synthroid<\/span><\/a> are both brand-name drugs. Tirosint is available in capsule and liquid form. Its liquid form is called Tirosint-Sol. Both the Tirosint capsules and Synthroid tablets are available in generic formulations, but Tirosint-Sol liquid does not have a generic version. Both medications come in various <\/span>doses<\/span><\/a>, as shown in the chart below. These medications are approved for use in adults and children.<\/span><\/p>\n

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Compare Tirosint vs. Synthroid key differences<\/span><\/h3>\n<\/th>\n<\/tr>\n<\/thead>\n

<\/td>\nTirosint<\/b><\/td>\nSynthroid<\/b><\/td>\n<\/tr>\n
Drug class<\/b><\/td>\nThyroid replacement hormone<\/span><\/td>\nThyroid replacement hormone<\/span><\/td>\n<\/tr>\n
Brand\/generic status<\/b><\/td>\nCapsules: Brand and generic<\/span><\/p>\n

Liquid: Brand only, called Tirosint-Sol<\/span><\/td>\n

Brand and generic<\/span><\/td>\n<\/tr>\n
What is the generic name?<\/b><\/td>\nLevothyroxine, also known as levothyroxine sodium<\/span><\/td>\nLevothyroxine, also known as levothyroxine sodium<\/span><\/td>\n<\/tr>\n
What form(s) does the drug come in?<\/b><\/td>\nOral capsules (13 mcg, <\/span>25 mcg, 37.5 mcg, 44 mcg, 50 mcg, 62.5 mcg, 75 mcg, 88 mcg, 100 mcg, 112 mcg, 125 mcg, 137 mcg, 150 mcg, 175 mcg, and 200 mcg)\u00a0<\/span><\/p>\n

Oral liquid\u00a0<\/span><\/td>\n

Oral tablets (<\/span>25 mcg, 50 mcg, 75 mcg, 88 mcg, 100 mcg, 112 mcg, 125 mcg, 137 mcg, 150 mcg, 175 mcg, 200 mcg, and 300 mcg)<\/span><\/td>\n<\/tr>\n
What is the standard dosage?<\/b><\/td>\nVaries; dose is individualized<\/span><\/p>\n

The capsule is taken once daily, on an empty stomach, 30\u201360 minutes before breakfast, with a full glass of water. The capsule should be swallowed whole.<\/span><\/p>\n

The liquid is taken once daily, 15 minutes before breakfast.\u00a0<\/span><\/td>\n

Varies; dose is individualized<\/span><\/p>\n

The tablet is taken once daily, on an empty stomach, 30\u201360 minutes before breakfast, with a full glass of water.<\/span><\/td>\n<\/tr>\n

How long is the typical treatment?<\/b><\/td>\nLong-term; lifelong<\/span><\/td>\nLong-term; lifelong<\/span><\/td>\n<\/tr>\n
Who typically uses the medication?<\/b><\/td>\nCapsules: Adults and children 6 years and older<\/span><\/p>\n

Liquid: Adults and children, including infants<\/span><\/td>\n

Adults and children, including infants (For pediatric patients who cannot swallow a pill, the tablet must be crushed and mixed with water, breast milk, or formula, since there is no liquid version available)<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

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Tirosint vs. Synthroid: Conditions treated<\/span><\/h2>\n

Thyroid hormone<\/span><\/a> is part of the endocrine system and plays a large role in metabolism, growth, and development. The term \u201cthyroid hormone\u201d actually represents a combination of the two main hormones released by the thyroid\u2014a small, butterfly-shaped gland at the front of your neck. Those two hormones are thyroxine (T4) and triiodothyronine (T3).<\/span><\/p>\n

T4 is mostly inactive, and T3 is active. When the thyroid releases T4, the body converts it into T3 in order to use it. Tirosint and Synthroid both replace the amount of T4 that the body is missing. These medications are often prescribed by primary care providers or endocrinologists to treat an underactive thyroid or thyroid cancer. Symptoms of hypothyroidism may include:<\/span><\/p>\n