Synthroid: Giving Life to Your Metabolism
Synthroid is a compound based on Sodic Levothyroxine, which has been on the market for several years. This drug is the synthetic basis of Thyroxine, also called T4, one of the most important hormones in our body.
All humans have a small gland at the base of the neck called Thyroid, which, from important minerals such as iodine and the stimulation of other substances such as TSH (thyrotropic), can produce the hormone T3 and T4, two compounds essential for the proper functioning of our body.
Thyroxine and Triiodothyronine are in charge of regulating our metabolic processes - how we administer our energy- especially its speed. When our body needs to increase the rate of our processes, the brain triggers a set of reactions that increase the amount of TSH in our body, therefore, there is greater esteem in our thyroid and produces more of this hormone.
Synthroid, as mentioned above, is a compound based on T4, Thyroxine. Although our thyroid produces both hormones and what we are looking for is to supply the hormonal demand in pathologies where there is a deficit such as Hypothyroidism, the T3 can become T4 in our tissues, so we only need to supply the demand of Thyroxine.
The mechanisms that regulate the thyroid are quite complex and delicate. Both excess and depletion of these hormones levels can trigger alterations in our organism that can lead to death.
With hypothyroidism, due to different causes, there is a decrease in T3 and T4 levels. Initially, an increase in thyroid stimulating hormone, TSH, partially controls this hormonal decrease, which gives rise to "subclinical Hypothyroidism". However, when the deficiency exceeds the body’s ability to compensate that loss is when the real Hypothyroidism arises.
This pathology is the main reason for medications such as Synthroid, primarily aimed at meeting the physiological needs of thyroid hormone.
Mechanism of Action – How It Works
Despite what most people consider, Synthroid is a hormone specially designed for our body, with good absorption and efficient conversion.
Thyroxine is the thyroid hormone par excellence, but it does not really have much effect on tissues. The main one in charge of acting at the target organs is T3, which executes its actions directly on the cells.
However, T4 travels easier through the bloodstream and is the ideal hormone T3 precursor, so it can transform itself into T3 as needed. It functions as a walking reservoir of thyroid hormone, which appears in quantities necessary to regulate the metabolic processes that take place in our body.
When we suffer from Hypothyroidism, we must compensate the deficit caused by the base alterations. Here, your doctor gradually replenishes those hormones using small doses and ascending to get the circulating dose you need.
Precautions about Using Synthroid
1) Allergies: In case of suffering any hypersensitivity reaction to any of this medicine compounds, please discontinue or avoid its use. If this drug consumption is necessary, please consult your physician as soon as possible.
Allergic reactions to Synthroid can be lethal, so it is best to start with small doses of 25mcg to confirm whether we are allergic to this drug.
Some of the symptoms related to allergic reactions are asthma attacks, where there is great difficulty breathing along with coughing spells, swelling in certain regions of the body, especially the face, hives and possibly, which is the most serious complication, anaphylactic shock.
2) Cardiovascular diseases: There is a relationship between Synthroid use and increased cardiovascular risk. This medicine, due to the effect it has, can aggravate the diverse cardiac disorders you have, especially arterial hypertension. Your doctor should use low initial doses and perform several checks on your blood pressure to make sure your values stay normal. If there is any alteration, you should decrease the doses of Levothyroxine immediately.
In addition, thyroid hormones can act as "stressful" factors, which means they increase the cardiac activity, and therefore, if you suffer from any type of arrhythmia or suffered a recent heart attack, it is better not to take this medication. In arrhythmias and cardiac ischemic events, what we seek is to maintain our frequency in a normal range, therefore, ideally, take none medication that can alter the rhythm of your heart.
3) Diabetes Mellitus: As mentioned above, this hormone triggers "stress" type responses in our body, so it increases almost everything. Under normal conditions, when someone is under a situation of physiological stress, blood sugar levels increase to improve the response we have to that event. In the case of Levothyroxine, the same thing happens, so it is necessary that your doctor readjust insulin doses or your diabetes medications, and thus be able to compensate the effect of the Synthroid.
4) Hypothyroidism: An important detail to consider is that people who have Hypothyroidism usually go a long time without medication until a physician diagnose them. By lowering the hormone levels of T3 and T4, we not only raise TSH concentration - to stimulate the gland to produce more thyroid hormones - but we also have other types of responses, including on the receptors of these hormones. These proteins receive the Thyroxine in the cell. When thyroid hormones levels decrease, the number of receptors increases so that the uptake - of the little thyroxine left circulating in the blood - is greater. Therefore, we can be very sensitive to the use of Levothyroxine the first time we take it, so it is necessary to use very low doses and then go up progressively.
Dosage – Getting the Right Amount
The dosage and the way we use this medicine depends on the person that is going to use it. Your doctor will consider certain factors to prescribe it, such as age, weight, heart comorbidities, pregnancy, drug interactions, and a specific diet presence. The individualization of the dose is a crucial aspect carried out by any doctor before prescribing such a delicate medicine to any patient.
Quick Tips about Synthroid
- Better on an empty stomach: We absorb Synthroid much better with an empty stomach thanks to the acidic environment created in it. Ideally, take your tablet at least 30-60 minutes before any meal, especially breakfast, since any food will interfere with its absorption.
- Drink water: Drink at least one whole glass of water (about eight ounces) with your tablet to improve absorption.
- Weight: Remember that, as mentioned above, they base Levothyroxine doses on weight, so if you lose weight your doctor should readjust it. This is a common situation in people suffering from Hypothyroidism treated with levothyroxine, since they lose weight quickly.
- Keep using your medicine at all times. Even though you see a rapid improvement, use your medicine in the prescribed doses, regardless of the situation. We can see the maximum tablet effect at 4-6 weeks; however, this is a medication for the rest of your life.
- Store your medicines at room temperature.
- Do not share this medication with others even if they have the same pathology as you.
- If you miss a dose, adapt to the next tablet. That is, if it has been a short time since you missed it, take it. However, if it has been a long time and the next tablet is next, you had better wait.
- Overdose: In case of symptoms such as tremors, cramps, chest pain, anxiety attack, palpitations or other abnormal reactions, consult your doctor quickly or go to the nearest emergency service.
It is difficult to administer this type of hormones to any patient, it is necessary to control the dose and time of use; therefore, your doctor will indicate several tests at certain times. The purpose is to know if the drug is keeping effect, and if not, determine whether it is due to the dose, absorption, failure of doses, drug interactions or multiple other causes.
Adults: in this case, it is important to keep controls by measuring the TSH in blood, our marker par excellence. In principle, it should be weekly until we reach the stable value, then at 6-8 weeks and then at least every 3 months during the first year. Subsequently, your doctor will indicate this type of tests at least once a year, with any thyroid echo or other studies he considers important.
Children: As pediatric patients always deserve a delicate control, we have to use more than a TSH serum quantification, and in order to do it, we have to measure the levels of T4. At least during the first week, the control should be exhaustive, not only on the dose but also on the proper compliance of the medication. Later, we will carry the same type of tests at similar intervals to those of the adult, up to the annual tests.
Side effects related to the use of this drug are like symptoms of hyperthyroidism since they usually occur from overdosing or from multiple doses. Among them, we have:
General: in principle, we observe general symptoms such as fatigue and fever caused by hormonal alterations, but later we have weight loss and increased appetite.
Central nervous system: At first, we have some unspecific symptoms such as a headache, and then we see others of hyperthyroidism like nervousness and irritability, as well as emotional instability and anxiety attacks. We rarely talk about seizures when it comes to this medication, even when the possibility exists.
Cardiovascular: Palpitations are the most commented symptom; however, we can have others complications like the myocardial infarction, arrhythmias, anginas of chest angina, cardiac arrest, etc. This is why we must be careful using Levothyroxine in patients with cardiovascular problems, not only can we increase and aggravate these basic problems, but we can seriously affect the life of the patient.
Gastrointestinal: similar to those observed in any medicine, such as vomiting, diarrhea, and nausea. It is probable that there are hepatic disorders caused by the excess of the metabolism of this hormone, however, it is not very frequent.
Dermatological: Alopecia and cutaneous rash.
Bones: Weight loss is not only due to alterations in fat or muscle metabolism, but also due to disorders that occur at the bone level. Density is a crucial factor affected in hyperthyroid processes, therefore, it is necessary to safeguard the doses and maintain constant control.
Reproductive: one of the most commented adverse effects is the alteration of fertility, where the probability of having children decreases due to the alterations caused by the Synthroid. It is necessary to emphasize that these disorders are temporary and do not cause long-term alterations. In the same way, we can observe alterations of the menstrual cycle in women.
Special Considerations about Using Synthroid
Pregnancy: Based on many studies carried out by specialists from various countries, we can safely state that Levothyroxine use is not dangerous during pregnancy. There are no reports of increases in the mortality rate or major congenital defects due to the use of this drug.
However, during pregnancy TSH levels increase, so it is necessary for your doctor to adjust the dose of Synthroid and constantly evaluate the levels of TSH in your blood. You do not need to discontinue or abandon your treatment; in fact, it can create major disruptions in your baby if you do.
Breastfeeding: There are a small number of studies focused on the effect of Levothyroxine in breast milk. It is possible to find tiny amounts of Synthroid, however, there is not enough data to corroborate that it harms the baby in any way. Treatment with the proper doses of this drug in the mother facilitates the secretion of breast milk. It is necessary that your doctor prescribe the exact doses, and seek to avoid any possible adverse effects that affect the baby.
Geriatric patients: Since the alterations caused by Levothyroxine are lethal, especially cardiovascular complications, it is necessary to use very small doses in older patients. Atrial arrhythmias are quite frequent in this type of patients, so it is necessary to take special care.
Hypothyroidism: Losing Control of Your Metabolism
All humans have a small gland of approximately 5 centimeters in diameter in our neck called Thyroid. This small organism regulates the speed of most metabolic processes through two hormones: T3 and T4.
In our body, there are metabolic reactions everywhere and almost at all times, therefore, so if there is an imbalance that alters these hormones, it is likely to affect almost all systems. In addition, Thyroid processes involve important connections with other glands such as the pituitary gland and regulatory centers such as the hypothalamus.
In hypothyroidism, we have alteration in the thyroid that does not allow it to function properly, so the levels of T3 and T4 decrease and we see the decline of metabolic processes.
Depending on the specific cause, it can be a fast or slow process, compensated by the increase in TSH, also called thyrotropin, the hormone in charge of stimulating the thyroid to increase T3 and T4 production. In this way, TSH puts the thyroid to work to the maximum to compensate for the hormonal loss, however, it has a limit and that is where real hypothyroidism begins.
The Metabolic Disorder Foundation
There are many causes ranging from autoimmune disorders – where we find the most common cause of this disease, called Hashimoto’s thyroiditis- to drug-related problems or alterations in iodine concentration.
In fact, many years ago there were epidemics of hypothyroidism related to people feeding. Iodine is a basic and fundamental primary resource for T3 and T4 formation, without it, people would have symptoms of hypothyroidism.
After these events, they added small amounts of iodine to the conventional salt so that people would consume this valuable mineral daily and avoid this type of hypothyroidism.
We will list the most important causes:
- Autoimmune diseases: Headed by Hashimoto’s thyroiditis, where the immune system, in charge of defending the organism, attacks the thyroid triggering an important damaging process.
- Thyroiditis: Related to alterations of the immune system or viral infections that cause primary lesions.
- Congenital: Although it is not frequent, it is the most common endocrine alteration in newborns. In this case, mothers do not consume enough iodine during pregnancy, which triggers the disorder in the baby.
- Medications: Some antiarrhythmics and antidepressants.
- Iodine deficiency
- Radioactive disorders: Radiation therapy is a delicate process that can lead to other complicated lesions, especially in the thyroid.
Classical Symptoms of Hypothyroidism
The onset of symptoms is quite slow, people often months or years before the disease develops. However, it is important to note that most of these symptoms are unspecific and we can confuse it with other pathologies. Thinking of hypothyroidism as a syndrome is what can bring us closer to the diagnosis.
Among the symptoms, we have:
- Apathy, indifference, or sometimes depression.
- Weight gain: because cells burn less energy.
- Dry skin and hair, with brittle, brittle hair and nails.
- Discovery of "bad" cholesterol levels in a general analysis.
- Tiredness and/or drowsiness.
- Reduced ability to concentrate, memory failures and mood alterations.
- Greater sensitivity to cold.
- Hoarse voice and swollen face.
- Muscle aches and/or cramps.
- Stiffness or swelling in the joints.
- Menstrual disorders.
When the disease becomes complicated, other more important symptoms appear such as heart failure, respiratory failure and generalized swelling. We call this condition myxedema or myxedematous coma, the most severe peak of conventional hypothyroidism.
Diagnosis: Finding the Abnormalities
Physicians can determine the presence and extent of hypothyroidism with four key tests:
TSH: as mentioned above, TSH is the precursor hormone of T3 and T4, is the one in charge of activating the thyroid to continue producing these hormones. When the difference in level starts due to the decrease, TSH production increases in order to counteract this effect. Therefore, TSH determination is an important key value, not only to determine the presence of hypothyroidism but also to know its magnitude and guide us based on the possible etiological cause.
Hormonal determination: of course, the direct determination of the hormonal levels of T3 and T4 is also useful; is an indispensable diagnostic test that the physician should request from any suspicious patient. Even so, this is not the study par excellence, but TSH measurement, since we can achieve the hormones levels in normal parameters thanks to TSH and thyroid effort to increase their production, therefore, these values may not be the best on their own to determine if there is an alteration, although they are ideal for supervising treatment.
Thyroid ultrasound: with goiter, which is the increase in the size of the thyroid due to the chronic increase in its functioning or autoimmune alterations that have lived within it, we recommend a thyroid echo to analyze extension degree and the pathology effect.
Thyroid Gammagraphy: This is a study requested because it allows us to analyze the structural and functional alterations of the thyroid. With Hashimoto thyroiditis, for example, is one of the indispensable studies that allow us to measure involvement degree of the thyroid. We can also use it for the diagnosis of enzymatic alterations and gland development. This study is important to diagnose and know possible malignant lesions.
Treatment: Replacement Therapy
Doctors limit the use of these hormones almost exclusively to direct repositioning when there is a deficit due to some extraordinary cause or pathology. The best way to do this is through medications that contain Thyroxine (T4). Although two thyroid hormones regulate the metabolism (T3 and T4), the thyroxine can become T3 in the target tissues of the body.
After the administration of this medication begins, we must be responsible and continue our treatment in order to establish the necessary levels that the individual needs of this hormone, or that we have to carry TSH and T4 controls out over a prolonged period.
Thyroid hormones deficit is especially important in children as these are essential for normal mental development and growth so physicians test all newborn children to confirm the proper functioning of the thyroid and if necessary start treatment immediately.
Goiter: The Reflection of a Thyroid Disorder
The goiter is a relevant and frequent thyroid complication, which usually looks like a tumor at the base of the neck, but it is only an increase of this gland’s size.
Although it is not an aberrant cell growth -as with tumors-, it is abnormal and usually the expression of some underlying pathology.
Some frequent pathologies that affect the thyroid, such as hyperthyroidism and hypothyroidism, trigger the abnormal growth of this gland, whether it abnormally raises T3 and T4 hormones production, or on the contrary diminishes it, autoimmune pathologies origin of these diseases- increase the size of the thyroid.
According to reputable organizations, goiter is a frequent finding in women and, if investigated by ultrasound, the frequency increases to 60% of cases in women over 60. It is also frequent throughout pregnancy.
It can also occur in men, although it is less common. Finally, we can observe it temporarily in newborn children of mothers treated during pregnancy with antithyroid drugs for hyperthyroidism. In addition, doctors often underdiagnose goiter, since it is difficult to detect the first degrees of this complication in obese people.
Causes behind Goiter
Mineral deficiency: The most common cause of goiter in endemic areas (those geographic areas in which it affects over 10% of the general population) is iodine deficiency since the body needs this micro-mineral to produce thyroid hormone. If it does not have enough, it enlarges to absorb as much as possible.
However, we have known this important cause for a long time, in fact, at the time it became a major epidemic. Today, to avoid this disease, large common salt companies include small amounts of iodine, which supply the basic needs of this mineral.
The body’s immune system attacks the thyroid gland (occurs in autoimmune problems such as Graves’ disease or Hashimoto’s thyroiditis; the latter is the most common cause of goiter in non-endemic areas).
Several substances can increase gland’s size, either certain drugs with iodine compounds (like lithium carbonate) or some foods (e.g. soy and vegetables of broccoli and cabbage family).
Smoking: proven by several studies, we can affirm that smoking is one of the most relevant risk factors in this complication development.
Infections: which give rise to some types of thyroiditis (inflammation of the thyroid gland).
Abnormal cellular growth: cysts, benign or malignant tumors. In fact, together with hypothyroidism and hyperthyroidism, it is one of the most frequent causes of goiter. Most of these neoplasms are benign; however, there is a high probability of malignancy, so we always consider removing the gland.
Signs and Symptoms of Thyroid Growth
Although the only goiter essential symptom is the neck base enlargement, where the thyroid is, there are other signs caused by the gland’s compression on the neck.
- Throat compression.
- Difficulties swallowing, especially solid foods.
- Difficulties in breathing, especially when the affected person raises his or her arms or lies on his or her back, with very large sizes.
- Pain in the thyroid area.
- Hoarseness or aphonia because of larynx’s compression, the organ in charge of voice emitting, or compression of the nerves that supply the larynx, such as the recurrent laryngeal nerve.
In addition, if the goiter produces an insufficient or excessive amount of thyroid hormones, symptoms of hypothyroidism or hyperthyroidism may appear.
How to Discover Goiter Cause
Doctors usually make goiter’s diagnosis with the physical examination because they find an enlarged thyroid gland. Since a goiter presence shows that there is an abnormality of thyroid gland, it is important to determine the cause.
As a first step, you will probably have thyroid function tests to determine if your thyroid is working too much or too little. Any other evaluations will depend on initial thyroid function tests results.
If your thyroid enlarges and you are hyperthyroid, your doctor will most likely perform tests to diagnose Graves’ disease. If you are hypothyroid, you may have Hashimoto’s thyroiditis and require additional blood tests to confirm this diagnosis.
One fundamental evaluation has to do with neck base ultrasound. With this study, we can orient ourselves about the specific cause, and test the neighboring structures commitment.
In addition, with a malignant pathology, the first diagnostic method that guides us is the ultrasound, since it allows us to detail certain malignant characteristics (cancer) in the thyroid’s growth.
Other tests that help diagnose goiter‘s cause may include a radioactive iodine gammagram or a fine needle puncture.
Getting Rid of Goiter – Treatment
Treatment depends on goiter‘s cause. If physicians relate it with dietary iodine deficiency, you will receive oral iodine supplements. This will reduce goiter’s size, although many times the goiter does not resolve.
If goiter‘s cause is Hashimoto’s thyroiditis, and you are hypothyroid, physicians will treat you with a daily thyroid hormone pill. This treatment will normalize your thyroid hormone levels but rarely makes the goiter go away.
Although the goiter usually shrinks in size, often too many scars on the gland do not allow it to shrink enough. However, treatment with thyroid hormone prevents the goiter from growing. Although it may be appropriate in some people, surgery is not a routine treatment for thyroiditis.
If you have goiter because of hyperthyroidism, treatment will depend on hyperthyroidism’s cause. Sometimes hyperthyroidism treatment can lead to the goiter complete disappearance. For example, treatment of Graves’ disease with radioactive iodine usually causes the goiter to disappear or decrease significantly.
Experts associate many goiters, such as multinodular goiter with normal levels of thyroid hormone in the blood. They require none specific treatment once they have made the diagnosis. If doctors suggest no specific treatment, they may tell you are at risk of developing hypothyroidism or hyperthyroidism.
However, if there are problems associated with thyroid gland’s size itself, such as when it puts pressure on the airways, your doctor may suggest removing the goiter through surgery.