eMedicine Specialties > Neurology > Neuromuscular Diseases
Thyroid Disease: Treatment & Medication
Updated: Jan 29, 2009
- Overview
- Differential Diagnoses & Workup
- Treatment & Medication
- Follow-up
Treatment
Medical Care
Neurologic manifestations in thyroid disease generally develop slowly. They are diagnosed months or years after initial endocrine problems.
- Patients seek care after developing characteristic systemic signs and symptoms.
- Polyneuropathy is rarely the initial manifestation of undetected hypothyroidism. Metastatic thyroid carcinoma rarely presents as an initial brain metastatic lesion.
- Chorea-ballism has been reported sporadically. Chorea has been associated with elevated levels of antithyroid antibodies, with the symptoms responding to oral steroid treatment.
- Interestingly, one study reports that mild hypothyroidism is associated with better survival of ambulatory elderly patients after acute stroke.5
- Several reports of intracranial vascular disease (arterial occlusion, superior sagittal sinus thrombosis, cerebral vein thrombosis) have been reported associated with both hypothyroidism and hyperthyroidism. However, the patients had multiple pathologies, and a clear correlation with thyroid disease is difficult to establish.6,7,8
Surgical Care
Surgery is indicated in the treatment of thyroid masses and large goiters.
Consultations
- Internal medicine/endocrinologist
- Head and neck surgeon
- Nuclear medicine specialist
- Radiation oncologist
- Pathologist
Diet
Iodine deficiency is not widespread in the United States, although immigrants from areas of endemic deficiency may require dietary consultation. Pregnant women may require more careful screening.
Activity
No restrictions are recommended typically.
Medication
The goal is to establish a euthyroid state. In hypothyroidism, this involves thyroid replacement, which is attained readily. In hyperthyroidism, elevated thyroid hormone is treated with surgery, which causes hypothyroidism and requires thyroid replacement, or with drugs and radioactive iodine.
Symptoms that are associated with abnormal thyroid states are treatable.
Thiourea derivatives
These medications are preferred for suppressing thyroid function.
Propylthiouracil (PTU)
Derivative of thiourea that inhibits organification of iodine by thyroid gland. Also inhibits conversion of T4 to T3, which is advantage over other agents.
Adult
300-450 mg/d PO divided tid; rarely, as much as 1600 mg/d may be required
Pediatric
Adjust dosage according to severity of disease and patient weight
Has anti-vitamin K activity and may potentiate activity of oral anticoagulants
Documented hypersensitivity; breastfeeding mothers
Pregnancy
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions
May cause rash, vasculitis, and rarely, hepatocellular damage and agranulocytosis; use sparingly in pregnant patients, because drug crosses placenta
Methimazole (Tapazole)
Suppresses thyroid function and has mechanism similar to that of PTU; does not inhibit peripheral conversion of T4 to T3.
Fifteen times as potent as PTU. PTU equivalent dosing can be used, divided tid.
Adult
Mild hyperthyroidism: 15 mg/d PO; adjust to effect
Moderately severe hyperthyroidism: 20-30 mg/d PO; adjust to effect
Severe hyperthyroidism: 60 mg/d PO; adjust to effect
Maintenance dose: 5-15 mg PO qd
Pediatric
Initial dose: 0.4 mg/kg PO divided tid
Maintenance dose: Half initial dose
Has anti-vitamin K activity and may potentiate activity of oral anticoagulants
Documented hypersensitivity; breastfeeding mothers
Pregnancy
D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus
Precautions
May cause agranulocytosis; closely monitor patients for adverse effects; may cause hypoprothrombinemia and bleeding
Beta-adrenergic blocking agents
These agents are used to treat symptomatic hyperthyroidism.
Propranolol (Inderal)
This nonselective, beta-adrenergic blocking agent treats symptomatic tachycardia. Has membrane-stabilizing activity and decreases automaticity of contractions.
Adult
20-40 mg PO q4-6h
Pediatric
2-4 mg/kg/d PO divided bid
Aluminum salts, barbiturates, NSAIDs, penicillins, calcium salts, cholestyramine, and rifampin may decrease bioavailability, possibly reducing effects
Conversely, calcium channel blockers, cimetidine, loop diuretics, and MAOIs may increase levels, and thus toxicity or effects
May increase toxicity of hydralazine, haloperidol, benzodiazepines, and phenothiazines
Documented hypersensitivity; uncompensated congestive heart failure (CHF); bronchial asthma; bradycardia; cardiogenic shock; AV conduction abnormalities
Pregnancy
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions
Caution in patients with renal or hepatic dysfunction (may reduce intraocular pressure); beta-adrenergic blockade may decrease signs and symptoms of acute hypoglycemia
Abrupt withdrawal may exacerbate symptoms of hyperthyroidism, including thyroid storm; withdraw drug slowly and monitor patient closely
Thyroid hormones
These agents are used in thyroid hormone replacement.
Levothyroxine (Synthroid, Levoxyl)
Synthetic, but identical to natural T4; in its active form, influences growth and maturation of tissues; is involved in normal growth, metabolism, and development.
Adult
25 mcg PO initially; increase to effect prn
Pediatric
10-15 mcg/kg/d PO initially; adjust to effect prn
Cholestyramine may decrease levothyroxine absorption; estrogens may decrease response to thyroid hormone therapy in patients with nonfunctioning thyroid gland; levothyroxine increases effect of anticoagulants; conversion of hypothyroid patient to euthyroid state may decrease activity of some beta-blockers
Documented hypersensitivity; uncorrected adrenal insufficiency; untreated thyrotoxicosis
Pregnancy
A - Fetal risk not revealed in controlled studies in humans
Precautions
Treatment of myxedema coma may require simultaneous administration of glucocorticoids; caution in patients with angina pectoris or cardiovascular disorders; monitor thyroid status periodically
Electrolytes
These agents replace depleted electrolytes.
Potassium chloride (K-DUR)
Essential for transmission of nerve impulses, maintenance of intracellular tonicity, and maintenance of normal renal function. Also vital for skeletal and smooth muscles. Replaces potassium lost in thyrotoxic periodic paralysis.
Adult
100-200 mEq PO during an attack
Pediatric
Administer as in adults
ACE inhibitors may elevate serum potassium concentrations; potassium-sparing diuretics and potassium-containing salt substitutes can produce severe hyperkalemia; hypokalemia may result in digoxin toxicity, use caution if discontinuing potassium preparation for patients who are maintained on digoxin
Hyperkalemia; renal failure and conditions in which potassium retention is present; oliguria or azotemia; crush syndrome; severe hemolytic reactions; anuria; adrenocortical insufficiency
Pregnancy
A - Fetal risk not revealed in controlled studies in humans
Precautions
High plasma concentrations of potassium may cause death due to cardiac depression, arrhythmias, or arrest; plasma levels do not necessarily reflect tissue levels
Monitor potassium replacement therapy whenever possible by continuous or serial ECG
Corticosteroids
These agents provide immunosuppressive therapy for Graves ophthalmopathy, especially in cases of severe exophthalmos.
Prednisone (Deltasone, Sterapred, Orasone)
Widely used glucocorticoid that suppresses inflammatory processes by reversing increased capillary permeability and suppressing PMN activity; used to treat allergic, inflammatory, and autoimmune disorders.
Adult
15-20 mg/d PO, although as much as 100 mg may be necessary; after obtaining satisfactory response, can be tapered slowly
Pediatric
Adjust dosage according to severity of symptoms (as in adult dosing)
Drugs that induce hepatic enzymes may increase clearance; estrogens may decrease clearance; may increase digitalis toxicity secondary to hypokalemia; phenobarbital, phenytoin, and rifampin may increase metabolism of glucocorticoids—in such cases, consider increasing maintenance glucocorticoid dose; diuretics may cause hypokalemia, monitor patients
Documented hypersensitivity; viral, fungal, or tubercular skin infections; peptic ulcer disease; hepatic dysfunction; connective tissue infections
Pregnancy
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions
Patients are at risk for multiple complications, such as severe infections; abruptly discontinuing glucocorticoids may cause adrenal crisis; complications of glucocorticoid use include hyperglycemia, edema, osteonecrosis, myopathy, peptic ulcer disease, hypokalemia, osteoporosis, euphoria, psychosis, myasthenia gravis, growth suppression, infections
Tricyclic antidepressants
These agents may help relieve painful polyneuropathy.
Amitriptyline (Elavil)
By inhibiting reuptake of serotonin and/or norepinephrine by presynaptic neuronal membrane, may increase synaptic concentration of these neurotransmitters in CNS; useful as analgesic for certain chronic and neuropathic pain.
Adult
10-100 mg PO qhs
Pediatric
<12 years: Not recommended
>12 years: Administer as in adults
Metabolized by P-450 2D6 system, so drugs that inhibit this enzyme system (eg, cimetidine, quinidine) may increase levels
Phenobarbital may decrease effects by increasing its metabolism; amitriptyline inhibits hypotensive effects of guanethidine; may interact with thyroid medications, alcohol, CNS depressants, barbiturates, and disulfiram
Documented hypersensitivity; MAOIs within past 14 d; caution in patients who have seizures, cardiac arrhythmias, glaucoma, or history of urinary retention
Pregnancy
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions
Schizophrenic patients may develop increased symptoms of psychosis; caution in patients with impaired liver function; lowers seizure threshold
Common adverse effects include antimuscarinic effects such as dry mouth, sedation, and blurred vision; others include orthostatic hypotension, increased appetite, and constipation; caution in patients who have seizures, cardiac arrhythmias, glaucoma, or history of urinary retention
Antiepileptic agents
These agents are useful in treating neuropathic pain.
Gabapentin (Neurontin)
Exact mechanism unknown. Structurally related to GABA; useful in some pain syndromes.
Adult
300-1200 mg PO tid
Pediatric
<12 years: Not established
>12 years: Administer as in adults
Antacids may reduce bioavailability significantly, so administer gabapentin at least 2 h following antacid; may increase norethindrone levels significantly
Documented hypersensitivity
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
Do not administer to patients with renal failure, since it is excreted by kidneys
More on Thyroid Disease |
| Overview: Thyroid Disease |
| Differential Diagnoses & Workup: Thyroid Disease |
 Treatment & Medication: Thyroid Disease |
| Follow-up: Thyroid Disease |
| References |
| « Previous Page | Next Page » |
References
Guimaraes J, Santos L, Bugalho P. Painful legs and moving toes syndrome associated with Hashimoto's disease. Eur J Neurol. Mar 2007;14(3):343-5. [Medline].
Chia SY, Chua R, Lo YL, Wong MC, Chan LL, Tan EK. Acute ataxia, Graves' disease, and stiff person syndrome. Mov Disord. Oct 15 2007;22(13):1969-71. [Medline].
Blanchin S, Coffin C, Viader F, Ruf J, Carayon P, Potier F, et al. Anti-thyroperoxidase antibodies from patients with Hashimoto's encephalopathy bind to cerebellar astrocytes. J Neuroimmunol. Dec 2007;192(1-2):13-20. [Medline].
Sinclair C, Gilchrist JM, Hennessey JV, Kandula M. Muscle carnitine in hypo- and hyperthyroidism. Muscle Nerve. Sep 2005;32(3):357-9. [Medline].
Alevizaki M, Synetou M, Xynos K, Alevizaki CC, Vemmos KN. Hypothyroidism as a protective factor in acute stroke patients. Clin Endocrinol (Oxf). Sep 2006;65(3):369-72. [Medline].
Dai A, Wasay M, Dubey N, Giglio P, Bakshi R. Superior sagittal sinus thrombosis secondary to hyperthyroidism. J Stroke Cerebrovasc Dis. Mar-Apr 2000;9(2):89-90. [Medline].
Ni J, Gao S, Cui LY, Li SW. Intracranial arterial occlusive lesion in patients with Graves' disease. Chin Med Sci J. Sep 2006;21(3):140-4. [Medline].
Peralta AR, Canhão P. Hypothyroidism and cerebral vein thrombosis--a possible association. J Neurol. Jul 2008;255(7):962-6. [Medline].
Adams RD, Victor M, Ropper AH. The endocrine myopathies. In: 6th ed. Principles of Neurology. 1997. New York: McGraw-Hill; 1440-2.
Ahdab R, Thomas D. Palatal tremor, focal seizures, repeated miscarriages and elevated anti-thyroid antibodies. Clin Neurol Neurosurg. Apr 2008;110(4):381-3. [Medline].
Avramides A, Papamargaritis K, Mavromatis I, et al. Visual evoked potentials in hypothyroid and hyperthyroid patients before and after achievement of euthyroidism. J Endocrinol Invest. 1992;15:749-753. [Medline].
Boyages SC, Halpern J-P. Endemic cretinism: toward a unifying hypothesis. Thyroid. 1993;3(1):59-69. [Medline].
Calza L, Aloe L, Giardino L. Thyroid hormone-induced plasticity in the adult rat brain. Brain Res Bull. 1997;44(4):549-57. [Medline].
Comi AM, Bellamkonda S, Ferenc LM, Cohen BA, Germain-Lee EL. Central hypothyroidism and Sturge-Weber syndrome. Pediatr Neurol. Jul 2008;39(1):58-62. [Medline].
DeLong GR. The neuromuscular system and brain in hypothyroidism. In: Braverman LE, Utiger RD, eds. Werner and Ingbar's The Thyroid: A Fundamental and Clinical Text. 7th ed. Philadelphia: Lippincott-Raven; 1996:826-35.
DeLong GR. The neuromuscular system and brain in thyrotoxicosis. In: Braverman LE, Utiger RD, eds. Werner and Ingbar's The Thyroid: A Fundamental and Clinical Text. 7th ed. Philadelphia: Lippincott-Raven; 1996:645-52.
Donati L, Antonelli A, Bertoni F, et al. Clinical picture of endemic cretinism in central Apennines (Montefeltro). Thyroid. 1992;2(4):283-290. [Medline].
Duhig TJ, McKeag D. Thyroid disorders in athletes. Curr Sports Med Rep. Jan-Feb 2009;8(1):16-9. [Medline].
Ferracci F, Carnevale A. The neurological disorder associated with thyroid autoimmunity. J Neurol. Aug 2006;253(8):975-84. [Medline].
Halpern J-P, Boyages SC, Maberly GF, et al. The neurology of endemic cretinism. Brain. 1991;114:825-841. [Medline].
Hsieh MJ, Lyu RK, Chang WN, Chang KH, Chen CM, Chang HS, et al. Hypokalemic thyrotoxic periodic paralysis: clinical characteristics and predictors of recurrent paralytic attacks. Eur J Neurol. Jun 2008;15(6):559-64. [Medline].
Jagannathan NR, Tandon N, Raghunathan P, Kochupillai N. Reversal of abnormalities of myelination by thyroxine therapy in congenital hypothyroidism: localized in vivo proton magnetic resonance spectroscopy (MRS) study. Brain Res Dev Brain Res. Aug 8 1998;109(2):179-86. [Medline].
Kurne A, Aydin OF, Karabudak R. White matter alteration in a patient with Graves' disease. J Child Neurol. Sep 2007;22(9):1128-31. [Medline].
Lai CL, Liu CK, Tai CT, et al. A study of central and peripheral nerve conduction in patients with primary hypothyroidism: the effects of thyroxine replacement. Kaohsiung J Med Sci. May 1998;14(5):294-302. [Medline].
Larsen PR. The thyroid. In: Wyngaarden JB, Smith LH Jr, Bennett JC, et al, eds. Cecil Textbook of Medicine. 19th ed. Philadelphia: Saunders; 1992:1248-71.
Losa M, Mortini P, Minelli R, Giovanelli M. Coexistence of TSH-secreting pituitary adenoma and autoimmune hypothyroidism. J Endocrinol Invest. 2006;29:555-559. [Medline].
Madeira MD, Cadete-Leite A, Andrade JP, et al. Effects of hypothyroidism upon the granular layer of the dentate gyrus in male and female adult rats: a morphometric study. J Comp Neurol. Dec 1 1991;314(1):171-86. [Medline].
Marta CB, Adamo AM, Soto EF, Pasquini JM. Sustained neonatal hyperthyroidism in the rat affects myelination in the central nervous system. J Neurosci Res. Jul 15 1998;53(2):251-9. [Medline].
Mavragani CP, Patronas N, Dalakas M, Moutsopoulos HM. Ill-defined neurological syndromes with autoimmune background: a diagnostic challenge. J Rheumatol. Feb 2007;34(2):341-5. [Medline].
Muthipeedika JM, Moosa A, Kumar A, Suchowersky O. Bilateral chorea--ballism associated with hyperthyroidism. Mov Disord. Apr 2005;20(4):512; author reply 512. [Medline].
Ozata M, Ozkardes A, Corakci A, Gundogan MA. Subclinical hypothyroidism does not lead to alterations either in peripheral nerves or in brainstem auditory evoked potentials (BAEPs). Thyroid. 1995;5(3):201-205. [Medline].
Ozata M, Ozkardes A, Dolu H, et al. Evaluation of central motor conduction in hypothyroid and hyperthyroid patients. J Endocrinol Invest. 1996;19:670-677. [Medline].
Ozkan Y, Colak R. Sheehan syndrome: clinical and laboratory evaluation of 20 cases. Neuro Endocrinol Lett. Jun 2005;26(3):257-60. [Medline].
Ozkardes A, Ozata M, Beyhan Z, et al. Acute hypothyroidism leads to reversible alterations in central nervous system as revealed by somatosensory evoked potentials. Electroencephalography and clinical neurophysiology. 1996;100:500-504. [Medline].
Parker RJ, Davidson AC. Hypothyroidism--an unexpected diagnosis following emergency treatment for heatstroke. Int J Clin Pract Suppl. Apr 2005;31-3. [Medline].
Perelman AH, Clemons RD. The fetus in maternal hyperthyroidism. Thyroid. 1992;2(3):225-228. [Medline].
Powner DJ, Boccalandro C, Alp MS, Vollmer DG. Endocrine failure after traumatic brain injury in adults. Neurocrit Care. 2006;5(1):61-70. [Medline].
Quattrini A, Nemni R, Marchettini P, et al. Effect of hypothyroidism on rat peripheral nervous system. Neuroreport. 1993;4:499-502. [Medline].
Sahni V, Gupta N, Anuradha S, Tatke M, Kar P. Thyrotoxic neuropathy- an under diagnosed condition. Med J Malaysia. Mar 2007;62(1):76-7. [Medline].
Somay G, Oflazoglu B, Us O, Surardamar A. Neuromuscular status of thyroid diseases: a prospective clinical and electrodiagnostic study. Electromyogr Clin Neurophysiol. Mar-Apr 2007;47(2):67-78. [Medline].
Tamburini G, Tacconi P, Ferrigno P, et al. Visual evoked potentials in hypothyroidism: a long-term evaluation. Electromyogr Clin Neurophysiol. 1998;38:201-205. [Medline].
Tuncel D, Cetinkaya A, Kaya B, Gokce M. Hoffmann's syndrome: a case report. Med Princ Pract. 2008;17(4):346-8. [Medline].
Further Reading
Keywords
thyroid neuropathy, thyroid myopathy, hyperthyroidism, hypothyroidism, Graves disease, myxedema, cretinism, thyrotoxicosis, Graves ophthalmopathy, thyroid eye disease, thyroid ophthalmopathy, thyroid orbitopathy, infiltrative ophthalmopathy, thyroid disease, T3, T4, thyroxine, thyroid hormones, regulation of thyroid hormones, myasthenia gravis, chronic thyrotoxic myopathy
