Pharmacological Treatment Options for HYPERTHYROIDISM
Ian Baker, PharmD Candidate 2007
Therapeutic Class/Agents Therapeutic Class/Agents Therapeutic Class/Agents Therapeutic Class/Agents
Thiourea drugs Iodides Beta Blockers
Product Brand/Generic Brand/Generic
Availability Adjuvant therapy to treat
Generic (Brand) Tapazole/methimazole-MMI SSKI/potassium iodide hyperthyroid metabolic
symptoms, not used for direct
Propylthiouracil-PTU (only available Potassium iodide (generic only) treatment of the disease.
as generic)
Mechanism
of Action Inhibits thyroid hormone synthesis Saturates the thyroid gland with
by blocking iodine binding sights on iodine and causes a decreased
monoiodotyrosine, diiodotyrosine, production of TH as the thyroid
and thyroglobulin gland must now focus energy into
processing the iodine. This effect
will last for a few days, and then
even more TH will be produced.
EFFICACY
Induces permanent Will suppress the
(Indication/Use, remission rates of 40-50%. production of TH for
Clinical Data Maximal response to 10days.
Support) medication takes 4-6months Iodine is most effective as
an adjuvant therapy and is
used to immediately induce
a euthyroid state until
thiourea drugs reach
therapeutic levels.
SAFETY *Contraindicated in patients using
*Major adverse effects occur in 1.5% eplerenone*
(Major Drug to 4.6% of patients.
Interactions, Major adverse effects:
Pre-cautions, Major adverse effects: Arrythmias
Contra- Benign transient leucopenia GI bleed
indications, Agranulocytosis Angioedema
Adverse Effects, Arthralgias Parotitis
Pregnancy Risk Use with caution if: Goiter
Category) Breastfeeding Thyroid adenoma
Pregnant
Have bone marrow Use with caution if:
suppression Allergic to iodine
Using agranulocytosis Hyperkalemic
Ian Baker, PharmD Candidate 2007 Pharmacotherapy Presentation – Pharmaceutical Care Rotation
University of Maryland School of Pharmacy Happy Harry’s Pharmacy Patient Care Center, Perryville, MD
agents Volume depleted (severe)
Impaired renal function Addison’s disease
Using hepatotoxic agents Hypothyroidism
Bronchitis, acute
*Caution when using with Renal Impairment
Amioderone CV disease
Pregnancy category: D Pregnancy category: D
Therapeutic Class/Agents Therapeutic Class/Agents Therapeutic Class/Agents Therapeutic Class/Agents
Dosage &
Administration Propylthiouracil Potassium Iodide (SSKI and generic
100mg PO qd-tid potassium iodide have the same
(Include renal Start 300-450mg PO div tid dosages) (1g/ml)
and/or hepatic
adjustments) Methimazole Thyroidectomy, pre-op
5-15 mg PO qd 50-250mg PO tid, start 10-
Start: 5-20mg PO q8h (give 14 days before surgery
with food) Hyperthyroidism (thyrotoxicosis)
*Hepatitis: avoid use* 50-500mg PO tid
Monitoring
*Monitor Every 4-8 weeks *Monitor in 1-2weeks (effects of the
(Efficacy and medication are short-acting)
Toxicity Efficacy
Parameters) resolution of signs and Efficacy
symptoms of resolution of signs and
hyperthyroidism symptoms of
hyperthyroidism
Toxicity
Monitor for signs of Toxicity -monitor for the following:
hypothyroidism Monitor for signs of
(bradycardia, lethargy, hypothyroidism
weight gain etc.) (bradycardia, lethargy,
Rashes that do not resolve weight gain etc.)
Unexplained body aches Allergic rxns: Itching, hives,
and muscle pains swelling, SOB
Confusion, numbness or
tingling in your hands, feet
or lips.
Ian Baker, PharmD Candidate 2007 Pharmacotherapy Presentation – Pharmaceutical Care Rotation
University of Maryland School of Pharmacy Happy Harry’s Pharmacy Patient Care Center, Perryville, MD
Patient
Education If taking methimazole tell Drink half a glass (4
patient to take with food ounces) of water when you
Observe body for rashes take this medicine.
that do not resolve (call Make sure your doctor
doctor) knows if you are pregnant
Pay attention to body or breast feeding
pains/muscle aches that do Report any unexplained
not resolve (call doctor) reactions or metallic taste to
Resolution of symptoms your physician
usually takes 4-6 weeks If you are allergic to
Inform doctor if you plan to shellfish, this medication
become pregnant. may cause allergy
Cost
(1-month) Propylthiouracil Potassium Iodide
50mg (90 ea): $13.24 1gm/ml (1 bottle, 240ml):
Methimazole $59.98
5mg (100ea): $68.76
10mg (100ea): $113.38
References
(Guidelines, Lexicomp Lexicomp
Drug Info Epocrates Epocrates
Sources) Drugdex Drugdex
American Association of American Association of
Clinical Endocrinologists Clinical Endocrinologists
medical guidelines for medical guidelines for
clinical practice for the clinical practice for the
evaluation and treatment of evaluation and treatment of
hyperthyroidism and hyperthyroidism and
hypothyroidism hypothyroidism
Ian Baker, PharmD Candidate 2007 Pharmacotherapy Presentation – Pharmaceutical Care Rotation
University of Maryland School of Pharmacy Happy Harry’s Pharmacy Patient Care Center, Perryville, MD