💊 Buy Synthroid Online Without Prescription

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Dr. Andrew H. Maran, MD Content Administrator Updated on: 11/08/2024 Next review: 11/02/2025

What is Synthroid?

Synthroid (the active ingredient is levothyroxine) is a thyroid medication that replaces a hormone normally produced by your thyroid gland to regulate the body's energy and metabolism. Levothyroxine is prescribed when the thyroid gland does not produce enough of this hormone on its own.

Synthroid treats hypothyroidism (low thyroid hormone).

Synthroid is also used to treat or prevent goiter (an enlarged thyroid gland), which can be caused by hormonal imbalances, radiation therapy, surgery, or cancer.

Important information

You may not be able to take synthroid if you have certain medical conditions. Tell your doctor if you have an untreated or uncontrolled adrenal disorder, a thyroid disorder called thyrotoxicosis, or if you have recent or ongoing symptoms of a heart attack.

Synthroid should not be used to treat obesity or weight problems. Dangerous side effects or death can occur from misuse of levothyroxine, especially if you are taking any other medications for weight loss or appetite suppression.

Before taking this medicine

Since thyroid hormone occurs naturally in the body, almost anyone can take synthroid. However, you may not be able to take this medication if you have certain medical conditions.

To make sure Synthroid is safe for you, tell your doctor if you have:

Thyroid disorder - thyrotoxicosis;
Heart disease, coronary artery disease, or a history of blood clots;
Diabetes (insulin or oral diabetes doses may need to be changed when you start taking synthroid);
Anemia (absence of red blood cells);
Osteoporosis or low bone mineral density;
Problems with the pituitary gland;
Any food or drug allergy;
Untreated or uncontrolled adrenal gland disorder;
If you have recently had a heart attack or have any symptoms of a heart attack (chest pain or heavy feeling, pain spreading to the jaw or shoulder, nausea, sweating, general bad feeling).

Tell your doctor if you have recently received iodine radiation therapy (eg, I-131).

Levothyroxine should not harm an unborn baby. If you become pregnant with synthroid, do not stop taking the medicine without your doctor's advice. Having low thyroid hormone levels during pregnancy can harm both mother and baby. Your doses may vary during pregnancy.

Levothyroxine can pass into breast milk, but it is not expected to be harmful to a nursing baby. Tell your doctor if you are breastfeeding. Your dosage needs may differ while you are breastfeeding.

Do not give this medication to a child without medical advice.

How should i take Synthroid?

Take Synthroid exactly as prescribed by your doctor. Follow all directions on the prescription label. Your doctor may occasionally change your dose. Do not take this medicine in larger or smaller amounts, or for longer than recommended.

Synthroid works best when taken on an empty stomach, half to one hour before breakfast. The absorption of levothyroxine is increased on an empty stomach. Follow your doctor's instructions and try to take your medicine at the same time every day.

If a child is using this medication, tell the doctor if the child has any changes in weight. Levothyroxine doses are based on weight in children and any changes may affect your child's dose.

It may take several weeks before your body begins to respond to Synthroid. Keep using this medicine even if you feel well. You may need levothyroxine for the rest of your life.

While using Synthroid, you may need frequent medical tests. Tell any doctor or dentist who treats you that you are using this medication.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it's almost time for your next scheduled dose. Do not take additional medication to make up for a missed dose.

What happens if I overdose?

Overdose symptoms may include headache, leg cramps, tremors, feeling nervous or irritable chest pain, shortness of breath, and fast or pounding heartbeats.

What should i avoid while using Synthroid?

Some medicines can make levothyroxine less effective when taken at the same time. If you are using any of the following drugs, do not take them within 4 hours before or 4 hours after taking levothyroxine:

Calcium Carbonate (Alka-Mints, Shell Oyster for Calcium, Calcite, Os-Cal, Calcium Calcium Shell, Soft Chew Rolaids, Tums, etc.);
Cholestyramine, colestipol;
Iron supplementation;
Sucralfate;
Sodium polystyrene sulfonate (kaleksat, kayeksalat, kionek);
Antacids containing aluminum or magnesium - Acid Gone, Gaviscon, Maalox, Magnesia Milk, Mintox, Mylanta, Pepcid Complete and others).

Avoid the following foods that can cause your body to absorb less levothyroxine: soy formula for newborns, cottonseed meal, walnuts, and high fiber foods.

Syndromic side effects

Get emergency medical help if you have signs of an allergic reaction to Synthroid; Labored breathing; Swelling of the face, lips, tongue, or throat.

Call your doctor right away if you have any serious side effects such as:

Fast or irregular heart rate;
Chest pain, feeling short of breath;
Fever, hot flashes, sweating;
Feeling unusually cold;
Weakness, tiredness, trouble sleeping (insomnia);
Memory problems, feeling depressed or irritable;
Muscle pain;
Dry skin or hair, hair loss;
Changes in menstruation;
Vomiting, diarrhea, changes in appetite, weight changes.

Common synthroid side effects may include:

Leg cramps, muscle weakness;
Headache;
Feeling jittery or irritable;
Diarrhea;
Skin rash, mild hair loss.

This is not a complete list of side effects and others may arise. Ask your doctor about side effects. You can report side effects to the FDA at the 1-800-FDA-1088 level.

What other drugs will affect synthroid?

Many other medications can be affected by thyroid hormone levels. Other medicine may also increase or decrease the effects of Synthroid.

Many medicines can interact with levothyroxine, and not all possible interactions are listed in this Medication Guide.

Tell your doctor about all medicines you use, start using, or stop using during Synthroid treatment. This includes prescription, over-the-counter, vitamin and herbal products. Share a list of all your medicines with any health care provider who treats you.