INTRODUCTION:

The thyroid is an important part of the human endocrine system, which are responsible for regulation of oxygen use, basal metabolic rate, cellular metabolism and growth and development.¹The thyroid gland secretes thyroxine (T4) and tri iodothyronine (T3), which are needed for proper growth and development and which are primarily responsible for determining the basal metabolic rate. The thyroid hormones are transported through the blood and act at the cellular level. Through the activation of genes, thyroid hormones stimulate protein synthesis, promote maturation of nervous system, and increase the rate of cell respiration in tissues, thus elevating the Basal Metabolic Rate (BMR).² The variations in the levels of these hormones lead to disturbed BMR and presents with signs and symptoms which are systemic in nature.

Thyroid disease is one of the commonest endocrine disorders worldwide. According to a recent projection from various studies, it has been estimated that about 42 million people in India suffer from thyroid diseases. About 1 to 2% of the adult population is known to suffer from thyroid disorders.³

The need to combat this dysfunction has risen in recent years due to its increasing prevalence. Hormone replacement has been the choice of therapy. However, alternative medicinal approaches are gaining popularity in view of their efficacy with minimal side effects. This review throws light on various drugs of plant origin which have proven action on thyroid and its functioning and also on the various factors associated with thyroid dysfunction.

Thyroid Dysfunction

There is increasing evidence that environmental exposures, specifically to pesticides, should also be considered potential risk factors for thyroid disease. Certain insecticides, herbicides, and fungicides, should also be considered potential risk factors for thyroid disease, reported to be endocrine disruptors and more specifically, thyroid disruptors acting through diverse mechanisms such as inhibition of thyroidal iodine uptake, interference at the thyroid hormone receptor, binding to transport proteins, interference with iodothyronine deiodinases, increased clearance of thyroid hormones, interference with cellular uptake of thyroid hormones and interference with thyroid hormone gene expression.⁴

The signs and symptoms of hypothyroidism and hyperthyroidism are often non specific and vague if present. Measurement of TSH, T3 and T4 in serum is important for diagnosis of overt and subclinical thyroid dysfunction.⁵ The decreased levels of thyroid hormones lead to hypothyroidism. Hypothyroidism presents with symptoms such as dry skin, decreased sweating, myxedema, puffy face with edematous eyelids, non pitting pretibial edema, pallor, retarded nail growth, dry brittle hair, constipation, weight gain, decreased libido and menstrual disturbances menorrhagia in common, oligomenorrhoea or amenorrhoea in long standing cases.⁶ Hyperthyroidism is caused as a result of excessive thyroid function often hyperthyroidism is considered synonymous with thyrotoxicosis (a state of thyroid hormone excess). However, thyrotoxicosis is usually secondary to graves’ disease, toxic multinodular goitre and toxic adenomas. Hyperthyroidism presents with exophthalmos, increased BMR, hyperactivity, dysphoria, irritability, muscular weakness, nervousness, palpitation, fatigue, weight loss with increased appetite, diarrhoea, polyuria, warm moist skin and Tremor.⁷

Classification of different forms of thyrotoxicosis⁸

With hyperthyroidism

Common forms:

Graves’ disease,

Toxic adenoma,

Toxic multinodular goiter,

Iodine-induced thyrotoxicosis.

Uncommon forms:

Congenital hyperthyroidism,

Hashitoxicosis,

TSH-secreting pituitary adenoma,

Trophoblastic tumours,

Metastatic thyroid carcinoma,

Struma ovarii.

Without hyperthyroidism

Common forms:

Sub-acute (De Quervain’s thyroiditis),

Painless thyroiditis,

Post-partum thyroiditis,

Iodine-induced thyrotoxicosis,

Uncommon forms:

Thyrotoxicosis factitia,

Iatrogenic thyrotoxicosis.

Adverse Effect of Antithyroid Drugs

Thyroid hormone, especially thyroxine, are widely used either at replacement doses to correct hypothyroidism or at suppressive doses to abolish thyrotropin (thyroid-stimulating hormone) secretion in patients with differentiated thyroid carcinoma after total thyroidectomy or with diffuse/ nodular nontoxic goitre. In order to suppress thyrotropin secretion, it is necessary to administer slightly supraphysiological doses of thyroxine. Possible adverse effects of this therapy include cardiovascular changes (shortening of systolic time intervals, increased frequency of atrial premature beats and, possibly, left ventricular hypertrophy) and bone changes (reduced bone density and bone mass), but the risk of these adverse effects can be minimised by carefully monitoring serum free thyroxine and free liothyronine (triiodothyronine) measurements and adjusting thedosage accordingly. Thionamides [thiamazole (methimazole), carbimazole, propylthiouracil] are the most widely used antithyroid drugs. They are given for long periods of time and cause adverse effects in 3 to 5% of patients. In most cases, adverse effects are minor and transient (e.g. skin rash, itching, mild leukopenia). The most dangerous effect is agranulocytosis, which occurs in 0.1 to 0.5% of patients. This life-threatening condition can now be effectively treated by granulocyte colony-stimulating factor administration. Other major adverse effects (aplastic anaemia, thrombocytopenia, lupus erythematous-like syndrome, and vasculitis) are exceedingly rare.⁹

Herbs Used as Antithyroid Drugs

A large number of herbs act as anti-thyroid activity in both thyroid diseases hypothyroidism and hyperthyroidism. In our review, we have tried to summarize few anti-thyroid herbs which have been described below. Mainly different phytoconstituents have different mechanism of action and uses against for both thyroid diseases as reported by different author have studied under each medicinal plants / herbs.

Some important plants used for treatment of thyroid disease are discussed below:

Withania somnifera (Ashwagandha)¹⁰

The study was performed to evaluate the anti-hypothyroidism potential of ashwagandha methanolic extract (AME). This target was performed through induction of animal model of hypothyroidism by propylthiouracil. After 1 month from treatments, blood samples were collected for biochemical determinations, and liver and kidney were removed for the determination of oxidative stress markers and thyroid gland was removed for histopathological examination. The total phenolic compounds in the extract and the in-vitro radical scavenging activity of extract were also determined. The results revealed that the induction of hypothyroidism by propylthiouracil induced a significant increase in serum TSH level but it induced significant decreases in the levels of total T3, free T3, free T4, and total T4 hormones compared with the control values. Also, serum glucose, IL-6, and body weight gain increased significantly while Il-10 and blood hemoglobin levels showed significant decrease. Induction of hypothyroidism increased also the levels of hepatic and renal MDA and NO and decreased significantly the values of GSH, GPx and Na⁺/ K⁺-ATPase. Both AME and the anti-hypothyroidism drug significantly ameliorated the changes occurred in the levels of the above parameters and improved histological picture of thyroid gland but with different degrees; where ashwagandha methanolic extract showed the strongest effect. We can conclude that ashwagandha methanolic extract treatment improves thyroid function by ameliorating thyroid hormones and by preventing oxidative stress.

Commiphora mukul (Guggle)¹¹

Many more like botanical name of herbal thyroid stimulant, Gum guggle is Commiphora mukul. The yellow resinous extract derived from the stem part of Mukul myrrh tree consists of volatile oils and resins in abundance. The active compound in Guggle is called guggulsterone and has the power to influence thyroid function and improve the condition of hypothyroidism. An added advantage of having the herb is a decrease in the level of harmful cholesterol, one of the features of hypothyroidism. The incidence of side effect is low, but can range from headache, gastric upset, skin rash and rarely, hiccups .

Camellia sinensis (Green Tea)¹²

Polyphenolic flavonoids, specially catechins are major constituents of tea. Antithyroidal and goitrogenic effect of flavonoids have been reported Green tea is derived from the tea leaves of Camellia sinensis and widely consumed globally. The green tea extracts (GTE) at different concentrations (1.25g% a” 5 cups of tea/ day; 2.5g% a” 10 cups of tea/ day and 5.0g% a” 20 cups of tea/ day) were orally fed to male rats for 30 days. Similarly, pure catechin was administered orally to male albino rats for 30 days at doses of 25, 50 and 100 mg/kg body weight that are equivalent to above doses of green tea extract in terms of its total catechin content and the morphological and functional changes of the thyroid have been investigated. The overall results reveal that oral administration of green tea extract at 2.5g% and 5.0g% concentrations for 30 days changed the morphology and histology resembling hypertrophy of thyroid follicles with differential colloid sizes as found in hypothyroid due to environment influences associated with significant inhibited activities of thyroid peroxidase(TPO) and 5’ monodeiodinase (5’ DI1) with elevated Na+,K+ ATPase and concomitant decrease in serum thyroxine (T4), triiodothyronine (T3) and increase in serum thyrotropin (TSH) levels developing a state of absolute biochemical hypothyroidism. All these suggest that catechin present in green tea has the antithyroidal as well as goitrogenic potential and its regular consumption at relatively high doses pose a threat to the functioning of thyroid.

Scutellaria baicalensis¹³

This study was performed to evaluate the anti-hyperthyroidal effects and action mechanism of Scutellaria baicalensis Georgi (SB), a medicinal herb, on levothyroxine (LT4)-induced hyperthyroidal rats. Compared with the Control group, pulse rate, serum T3, T4, triglyceride, thyroid follicle size, and the deiodinase 1 (Dio1) gene expression were significantly reduced in the SB and PTU groups. Serum TSH and the thyroxine-binding globulin (Tbg) gene expression were significantly increased in the SB and PTU groups. These results suggest that SB might suppress T3, T4, and adrenergic activity by modulating Dio1 and Tbg expression, and therefore, SB could be an alternative therapy for hyperthyroidism.

Pennisetum millet¹⁴

Pearl millet [Pennisetum Millet (L.) leeke] is the main source of food energy for the rural poor in many areas of the semiarid tropics. Epidemiological evidence suggests that millet may play a role in the genesis of endemic goiter in these areas, and sparse experimental data in rats support this suspicion. This study was undertaken to determine in-vivo in rats and in-vitro using porcine thyroid slices and a thyroid peroxidase (TPO) assay the goitrogenic and antithyroid effects of millet diets, extracts of millet, and certain pure compounds contained therein. For use in these studies, whole grain millet was progressively dehulled to yield successively four bran and four flour fractions in which direct analyses revealed progressively lower concentrations of C-glycosyl flavones. In-vivo feeding of bran fraction 1, that richest in C-glycosyl flavones, led to a significant increase in thyroid weight and antithyroid effects. Feeding of bran fraction 2, the next richest in C-glycosyl flavones, produced similar, but less marked, changes. In-vitro studies of ¹²⁵I metabolism using porcine thyroid slices indicated that extracts of bran fractions 1 and 2 were most potent, producing changes similar to those produced by methimazole (MMI). At a concentration of 60 mmol/L, glucosylvitexin, the major C-glycosylflavone present in millet, had effects comparable to those of 1 mumol/L MMI. Similarly, in studies of porcine TPO, extracts of bran fraction 1 caused pronounced (85%) inhibition of enzyme activity, and progressively less inhibition was induced by extracts of bran fractions 2, 3, and 4. Overall, the TPO-inhibiting activities of the various millet fractions closely correlated with their C-glycosylflavone concentrations. Three C-glycosylflavones present concentrations. Three C-glycosylflavones present in millet, glucosylvitexin, glycosylorientin, and vitexin, also inhibited TPO activity. Thus, in-vivo and in-vitro studies revealed that millet diets rich in C-glycosylflavones produce goitrogenic and antithyroid effects similar to those of certain other antithyroid agents and small doses of MMI. We conclude that in areas of iodine deficiency in which millet is a major component of the diet, its ingestion may contribute to the genesis of endemic goiter.

Digitaria exilis¹⁵

Digitaria exilis (fonio) is a tiny variety of millet commonly eaten by inhabitants of semiarid regions. A sample of fonio collected right in the middle of a severely iodine-depleted goitrous endemic was submitted to phytochemical investigations in order to assess the potential contributory roles played by vegetable molecules to the goitrogenic processes. The total content of flavonoids amounts to 500 mg/kg of the edible whole cereal grains. Their extraction and identification fail to detect the C-glycosylflavones described in other millet varieties but point out the presence of apigenin (A = 150 mg/kg) and of luteolin (L₁ = 350 mg/kg). Ten percent of A and 80% of L₁ are present in free form, whereas the remaining 90% of A and 20% of L₁ are bound as O-glycosylflavones. Both A and L₁ aglycones manifest strong anti-thyroid peroxidase (TPO) activities, resulting in a significant reduction of the hormonogenic capacity of this enzyme. In addition, L₁ significantly depresses the cyclic AMP phosphodiesterase, implying a concomitant overproduction of the thyrotropin-dependent nucleotide. These last unreported data are regarded as counteracting to some extent the TPO-mediated goitrogenic properties of L₁. Since fonio is devoid of other molecules likely to interfere with the thyroid function, results are directly and causally attributed to A and L₁ found in the customary diet.

Lycopi europaei¹⁶

The aim of the prospective two-armed open study was to examine the effect of Lycopi europaei herb on thyroid function and on associated symptoms during a 3-month follow-up phase. The study population consisted of patients with a basal TSH<1.0 mU/l and hyperthyroidism-associated symptoms. For the first time, the T3/T4 excretion in 24 h urine was measured as a primary objective parameter. As secondary parameters, further hormones, the general condition and the symptoms associated with hyperthyroidism were registered. The urinary T4 excretion was significantly increased in Lycopus europaeus treated patients (p=0.032). It is supposed that renal mechanisms cause the increased T4 excretion either by a modification within the glomeruli or by impaired reabsorption. Symptoms being specific to the thyroid gland were diminished, as e.g. the increased heart rate in the morning. The Lycopus europaeus preparation showed a good tolerance. These findings confirm positive effects of Lycopus europaeus in slight forms of hyperthyroidism.

Melissa officinalis¹⁷

Several natural or synthetic chemicals have been indicated as potential thyroid disruptors. The development of in-vitro assays has been recommended to comprehensively assess the potential thyroid disrupting activity of a substance or a complex mixture. In this study, 12 substances suspected for acting as thyroid disruptors were tested for their ability to inhibit TSH-stimulated cAMP production in vitro. Those substances producing an inhibition were further studied to establish the level at which they interfere with this step of thyroid cell function. Using Chinese hamster ovary cells (CHO) transfected with the recombinant human TSH receptor, a dose-dependent inhibition of TSH-stimulated adenylate cyclase activity was produced by 1,1-bis-(4-chlorphenyl)-2,2,2-trichloroethan (DDT), Aroclor 1254 and Melissa Officinalis. All three substances also inhibited the cAMP production stimulated by TSH receptor antibody. Melissa Officinalis produced a significant inhibition of TSH binding to its receptor and of antibody binding to TSH, while no significant changes were produced by Aroclor 1254 or DDT in these assays. These data suggest that principles contained in Melissa Officinalis may block the binding of TSH to its receptor by acting both on the hormone and the receptor itself, while DDT and Aroclor 1254 affect cAMP production mainly at post-receptor step. In conclusion, A developed a set of in-vitro assays that allow investigation into the effect of thyroid disruptors on the TSH-mediated activation of the cAMP cascade. These assays may be useful to identify the mechanism of action of thyroid disruptors, coming beside and supporting animal studies or epidemiological surveys.

Carica papaya¹⁸

Activity of Carica Papaya seeds extract on the pituitary, thyroid and parathyroid glands of rats were investigated. The ethanolic extract of C. papaya seeds (50 and 200 mg/kg) was administered orally daily to sexually mature male wistar rats for one and eight weeks. Histology of pituitary and thyroids were prepared. The thyrotrophs (TSH cells) of anterior pituitary showed progressive hypertrophy and degranulation at high dose levels of 200 mg/kg for one and eight weeks respectively. Acidophils somatotrophs (STH cells) and Lactotrophs or prolactin cells (LTH/PRL cells) showed no significant changes in both the experimental groups as compared to control. However, the thyroid glands of rats that were treated with 200 mg/kg extract showed pronounced hypertrophy, hyperplasia and degranulation with many empty follicles devoid of colloid. The parathyroid glands appeared normal. These observations showed possible side-effects of the C. papaya seeds in rats.

Lycopus virginicus¹⁹

In one study, freeze-dried extracts (FDE) of L.virginicus and L.europaeus, and some of their oxidised constituents were shown to exert anti-thyrotropic activity by forming adducts with TSH, thus inhibiting its ability to bind to the TSH receptor. This inhibitory interaction has also been demonstrated for the Graves’ autoantibody in-vitro, which resembles TSH in its ability to bind to the thyroid plasma membrane and activate the gland, which is the proposed mechanism in the pathogenesis of Graves’ disease. This study examined the effect of FDE and their constituents on the binding and biological action of Graves’-IgG and found a dose-dependent decrease in TSH-binding inhibitory activity, suggesting that the active principles present in the FDE may interact with the Graves’-IgG to inhibit its ability to bind to the TSH receptor and activate the thyroid, as they do with TSH. The authors concluded that these findings provide possible rationale for the empirical use of FDE in the treatment of Graves’ disease.

Inula racemosa²⁰

The efficacy of Inula racemosa (root) and Gymnema sylvestre (leaf) extracts either alone or in combination was evaluated in the amelioration of corticosteroid-induced hyperglycaemia in mice. Simultaneously thyroid hormone levels were estimated by radio-immunoassay (RIA) in order to ascertain whether the effects are mediated through thyroid hormones or not. While the corticosteroid (dexamethasone) administration increased the serum glucose concentration, it decreased serum concentrations of the thyroid hormones, thyroxine (T4) and triiodothyronine (T3). Administration of the two plant extracts either alone or in combination decreased the serum glucose concentration in dexamethasone induced hyperglycaemic animals. However, the administration of Inula racemosa and Gymnema sylvestre extracts in combination proved to be more effective than the individual extracts. These effects were comparable to a standard corticosteroid-inhibiting drug, ketoconazole. As no marked changes in thyroid hormone concentrations were observed by the administration of any of the plant extracts in dexamethasone treated animals, it is further suggested that these plant extracts may not prove to be effective in thyroid hormone mediated type II diabetes, but for steroid induced diabetes.

Annona squamosa²¹

Annona squamosa (Custard apple) seeds are generally thrown away as waste materials. The extract of these seeds was evaluated for its possible ameliorative effect in the regulation of hyperthyroidism in mouse model. Serum triiodothyronine (T3), thyroxine (T4) concentrations, hepatic glucose-6-phospatase (G-6-Pase) and 50-mono-deiodinase (50DI) activity were considered as the end parameters of thyroid function. Simultaneously hepatic lipid peroxidation (LPO), superoxide dismutase (SOD) and catalase (CAT) activities were investigated to observe its hepatotoxic effect, if any. L-T4 administration (0.5 mg/kg/d for 12 days, i.p.) increased the levels of serum T3 and T4, activity of hepatic G-6-Pase, 50DI and LPO with a parallel decrease in SOD and CAT activities. However, simultaneous administration of the Annona seed extract (200 mg/kg) or quercetin (10 mg/kg) to T4-induced hyperthyroid animals for 10 days, reversed all these effects indicating their potential in the regulation of hyperthyroidism. Further, the seed extract did not increase, but decreased the hepatic LPO suggesting its safe and antiperoxidative nature. Quercetin also decreased hepatic LPO. When relative efficacy was compared with that of propyl thiouracil (PTU), a standard antithyroidic drug, experimental seed extract appeared to be more effective. Phytochemical analyses including HPLC revealed the presence of quercetin in the seed extract and the results on the effects of quercetin suggested the involvement of this phytochemical in the mediation of antithyroidal activity of Annona squamosa seed extract.

Azardirachta indica²²

In this investigation, the attempt were made to study the unstudied adverse effects of neem ( Azardirachta indica) leaf extract on the thyroid function of male mice. Neem leaf extract was orally administered in two different doses 40 mg and 100 mg kg day for 20 days. The extract exhibited differential effects. While the higher dose decreased serum. tri-iodothyonine (T₃)and increased serum thyroxine (T₄) concentrations, no significant alterations of levels were observed in the lower dose group, indicating that the high concentrations of neem extract can be inhibitory to thyroid function, particularly in the conversion of T₄to T₃ , the major source of T₃ generation. A concomitant increase in hepatic lipid peroxidation (LPO) and a decrease in glucose-6-phosphatase (G-6-Pase). activity in the higher dosed group also indicated the adverse effect of neem extract despite an enhancement in the activities of two defensive enzymes, superoxide dismutase (SOD) and catalase (CAT). Thus, it appears that the higher concentration of neem extract may not be safe with respect to thyroid function and lipid peroxidation.

Convolvulus pluricaulis²³

An investigation was made to evaluate the role of Convolvulus pluricaulis root extract in the regulation of hyperthyroidism in female mice. Its possible site of action was also studied. L-Thyroxine treatment for 30 days increased serum concentrations of thyroxine (T4) and triodothyronine (T3). The activity of hepatic 5-monodeiodinase (5-DI) and glucose-6-phosphatase (G-6-Pase) was also enhanced. On the other hand, administration of the plant extract either alone or with L-T4, decreased serum T3 concentration and the activity of hepatic 5-DI and G-6- phase, without marked alteration in hepatic lipid peroxidation, indicating the possible regulation of hyperthyroidism by the plant extract. It appears that the action of the plant extract on thyroid function is primarily mediated through the inhibition of 5-DI enzyme activity.

Fucus vesiculosus (Bladderwrack)²⁴

Many herbalists and naturopathic physicians have relied on seaweed species in the treatment of hypothyroidism predicated on their iodine content. Fucus vesiculosus or bladderwrack, for example, contains variable amounts of iodine, up to 600 mg/g. Much of the iodine content is organically bound, a more potent thyroid stimulating form than mineral bound iodine. There are case reports of seaweed, especially bladderwrack, causing both hypothyroidism and hyperthyroidism, and evidence suggests thyroid activity. However, there are no studies of efficacy, dosing, or safety to support its use, and no standardization of iodine content. Using sea-weeds with the rationale that its iodine content is what is affecting treatment may be erroneous, as most thyroid insufficiency in the United States is not attributable to iodine deficiency. Further, excess iodine, as discussed, can contribute to or worsen hypothyroidism. Bladderwrack may interfere with thyroid replacement therapies such as thyroxine. Bladderwrack also contains organically bound arsenic, which although rapidly excreted, should suggest caution when using large amounts.

Emblica officinalis²⁵

The role of Emblica officinalis L. and Bauhinia purpurea L. extracts in regulating thyroid functions was studied in male mice. Oral administration of Emblica officinalis L. fruit extract at 30 mg/kg body weight (b.wt.) each day for 20 days decreased serum T3 and T4 concentrations and hepatic O2 consumption. In contrast, daily administration of Bauhinia purpurea at 2.5 mg/kg b.wt. each day for 20 days increased serum T4 concentration and O2 consumption. Both the plant extracts exhibited hepatoprotective effects as evidenced by decreased lipid peroxidation. In animals treated with Emblica officinalis, activities of superoxide dismutase and catalase remained unaffected, but a significant increase in both of these antioxidative enzymes was observed in Bauhinia purpurea treated animals, indicating that extract of Emblica officinalis, but not the extract of Bauhinia purpurea, may have direct free radical scavenging role.

Ocimum sanctum²⁶

The effects of Ocimum sanctum leaf extract on the changes in the concentrations of serum triiodothyronine (T₃), thyroxine (T₄) and serum cholesterol; in the activities of hepatic. glucose-6-phosphatase (G-6-P), superoxide dismutase (SOD) and catalase (CAT) ; hepatic lipid peroxidation (LPO) and on the changes in the weight of the sex organs were investigated. While the plant extract at the dose of 0.5 g kg^-1 body wt. for 15 days significantly decreased serum T₄ concentrations, hepatic LPO and G-6-P activity, the activities of endogenous antioxidant enzymes, SOD and CAT were increased by the drug. However, no marked changes were observed in serum T₃ level, T₃/T₄ ratio and in the concentration of serum cholesterol. It appears that Ocimum sanctum leaf extract is antithyroidic as well as antioxidative in nature.

Moringa oleifera²⁷

The aqueous leaf extract of Moringa oleifera was evaluated for its ameliorative effect in the regulation of thyroidism in rat model. Male albino rats of 120-150 g were treated orally with doses of 500 mg/kg body weight (b.w.) and 250 mg/ kg b.w. of aqueous extract of Moringa oleifera leaf. Results show that T3 and T4 were increased and TSH was decreased significantly (p>0.05) at high doses compared to those in the control group. Also, the extract significantly reduced (p<0.05) total cholesterol concentration and low density lipoproteins cholesterol (LDL) concentration in the serum while it had no significant effect on serum High density lipoprotein (HDL) cholesterol concentration at all doses administered when compared with controls. The results of this study suggest that the extract may have beneficial effect on serum cholesterol concentration and a stimulant to thyroid functions

CONCLUSION:

The herbal approach to thyroid dysfunction is invariably necessary to avoid the various side effects of hormonal therapy. The herbal cure is gaining world wide acceptance and has emphasized the head of the modern scientific exploration and evaluation of ethno medicine from plants. There is need for clinical research of the above plant to certify their efficacy in normalising thyroid dysfunction. These will lead to remarkable discoveries from plant based ethno medicine.

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Received on 21.04.2020 Modified on 03.06.2020

Research J. Pharm. and Tech. 2020; 13(10):5045-5051.

DOI: 10.5958/0974-360X.2020.00884.7