Dosage

UCSF/SFGH/VASF Guidelines for Antimicrobial Use in Adults

February 16, 2013 Infectious Diseases, Pharmacokinetics No comments ,

Below is the guideline for adults antimicrobial use, including the renal impairment dosage adjustment. UCSF School of Pharmacy provides the information of this guideline and I translated portion of the table into Chinese. I hope this information will help anyone who need it.

Table 1 UCSF/SFGH/VASF Guidelines for Antimicrobial Use in Adults

成人抗微生物药物剂量调整
药物CrCl>50ml/minCrCl 10-50ml/minCrCl<10ml/min (ESRD not on HD)IHDCRRT备注
阿昔洛韦单纯疱疹病毒感染 5mg/kg/dose IV Q8h5mg/kg/dose IV Q12-24h2.5mg/kg IV Q24h2.5mg/kg IV*1,then 2.5mg/kg IV QPM(give post HD on HD days)5mg/kg IV Q24h
单纯疱疹病毒性脑炎/带状疱疹 10mg/kg/dose IV Q8h10mg/kg/dose IV Q12-24h5mg/kg IV Q24h5mg/kg IV*1,then 5mg/kg IV QPM5-10mg/kg IV Q12-24h
阿莫西林500-1000mg po TID250-500mg po BID250mg po QD暂缺暂缺
两性霉素B Dose on total body weight0.6-1.0mg/kg IV Q24h不变 不变 Dosage reductions in renal disease are not necessary.However,due to the nephrotoxic potential of the drug, reducing the dose or holding the drug in the setting of a rising serum creatinine may be warranted.Dosage reductions in renal disease are not necessary.However,due to the nephrotoxic potential of the drug, reducing the dose or holding the drug in the setting of a rising serum creatinine may be warranted.
两性霉素B脂质体 Dose on total body weight侵袭性霉菌感染 3-5mg/kg IV Q24h Doses up to 10mg/kg have been used for invasive mucormycosis 预防(heme-onc) 1mg/kg IV Q24h不变 不变 Dosage reductions in renal disease are not necessary.However,due to the nephrotoxic potential of the drug, reducing the dose or holding the drug in the setting of a rising serum creatinine may be warranted.Dosage reductions in renal disease are not necessary.However,due to the nephrotoxic potential of the drug, reducing the dose or holding the drug in the setting of a rising serum creatinine may be warranted.
阿米卡星>=60ml/min 15-20mg/kg/dose IV Q24h40-60ml/min 5-7.5mg/kg IV Q12h 20-40ml/min 5mg/kg IV Q12h-24h<20ml/min 5mg/kg loading dose (Consult pharmacy for maintenance dose)5mg/kg IV*1, then 3mg/kg IV post HD5mg/kg IV*1, then 3mg/kg IV Q24h
Dose is based on ideal body weight (IBW) except in obese patients or those under their ideal body weight. Use actual body weight if patient weight is less than IBW. Use adjusted body weight (ABW) in patients who are obese. Amikacin is generally used as a second-line aminoglycoside because of its increased cost and need to send out levels. (more…)

Make a provider and patient education for levothyroxine

February 13, 2013 Adverse Drug Reactions, Cardiology, Drug Informatics, Drug Interactions, Pharmacokinetics, Pharmacotherapy, Pharmacy Education, Therapeutics 3 comments , , , ,

Today I would like to write something about levothyroxine. My hospital uses levothyroxine often. Everyday there are lots of patients prescribed with levothyroxine. I do believe it is necessary to write below for education, which is not only for patients but also providers. The reference I use comes from U.S. FDA’s official drug information database.

Indications and Usage

Levothyroxine sodium is used for the following indications:

Hypothyroidism – As replacement or supplemental therapy in congenital or acquired hypothyroidism of any etiology, except transient hypothyroidism during the recovery phase of subacute thyroiditis. Specific indications include: primary (thyroidal), secondary (pituitary), and tertiary (hypothalamic) hypothyroidism. Primary hypothyroidism may result from functional deficiency, primary atrophy, partial or total congenital absence of the thyroid gland, or from the effects of surgery, radiation, or drugs, with or without the presence of goiter.

Pituitary TSH Suppression – In the treatment or prevention of various types of euthyroid goiters, including thyroid nodules, subacute or chronic lymphocytic thyroiditis, multinodular goiter and, as an adjunct to surgery and radioiodine therapy in the management of thyrotropin-dependent well-differentiated thyroid cancer.

Contraindications

Levothyroxine is contraindicated in patients with untreated subclinical (suppressed serum TSH level with normal T3 and T4 levels) or overt thyrotoxicosis of any etiology and in patients with acute myocardial infarction. Levothyroxine is contraindicated in patients with uncorrected adrenal insufficiency since thyroid hormones may precipitate an acute adrenal crisis by increasing the metabolic clearance of glucocorticoids. Finally, levothyroxine is contraindicated in patients with hypersensitivity to any of the inactive ingredients in levothyroxine.

Dosage and Administration

  • The goal of replacement therapy is to achieve and maintain a clinical and biochemical euthyroid state.
  • The goal of suppressive therapy is to inhibit growth and/or function of abnormal thyroid tissue.

To acheive the two goals above, it depends on variety of factors including the patient’s age, body weight, cardiovascular status, concomitant medical conditions (e.g., pregnancy, concomitant medications, and the specific nature of the condition being treated). As a result Dosing must be individualized and adjustments made based on periodic assessment of the patient’s clinical response and laboratory parameters.

Levothyroxine sodium tablets are administered as a single daily dose.

Table 1 The Indication and Dosages of Levothyroxine

Indication and UsageDosage
1HypothyroidismIndividuals who are at low risk of coronary artery diseaseStarting at 1.7 mcg/kg/day (Full dose). Adjusting dosage in 12.5-25 mcg increments until clinically euthyroid and serum TSH has normalized.
If myxedema coma, administer intravenously rather than orallyIndividuals older than 50 yrs or under 50 yrs with underlying cardiac diseaseStarting from 25-50 mcg/day, with increments of 12.5-25 mcg/day at 6-8 week intervals until clinical euthyroid and the serum TSH has normalized
Elderly individualsStarting from 12.5-25 mcg/day, with increments of 12.5-25 mcg/day at 4-6 week intervals until clinical euthyroid and the serum TSH has normalized
Individuals with severe hypothyroidismStarting from 12.5-25 mcg/day, with increments of 25 mcg/day at 2-4 week intervals until clinical euthyroid and the serum TSH has normalized
Secondary or tertiary hypothyroidismDosage as above but titrated until clinically euthyroid and serum free-T4 level is restored to the upper half of the normal range
2TSH Suppression – various types of euthyroid goiters and thyroid cancerWell-differentiated thyroid cancer> 2 mcg/kg/day (Target: TSH suppressed to <0.1 mU/L)
Contraindicated if the serum TSH is already suppressedWell-differentiated thyroid cancer (high risk)Target: TSH suppressed to <0.01 mU/L
Benign nodules and nontoxic multinodular goiter (controversial)Target: TSH suppressed to between 0.1 to either 0.5 or 1.0 mU/L

 

The adequacy of therapy is determined by periodic assessment of appropriate laboratory tests and clinical evaluation. In adult patients with primary (thyroidal) hypothyroidism, serum TSH levels alone may be used to monitor therapy. The frequence of TSH monitoring during levothyroxine dose titration depends on the clinical situation but it is generally recommended at 6-8 week intervals until normalization.

Monitor (more…)