Table 2. Laboratory Monitoring Interval (in Months) Recommended for Chronic Medications.
| Medication | Laboratory Monitoring Parameter | Interval Recommended by Pharmacists | Interval Recommended by Physicians | Interval Recommended by Nurse Practitioners | Interval Agreement Across Total Sample* |
|---|---|---|---|---|---|
| Acetaminophen at a dosage of > 4 grams | Serum liver function tests | 1 | 3 | 6 | No agreement about interval |
| Angiotensin II receptor blockers (e.g., losartan, valsartan) | Serum potassium level | 6 | 3 | 6 | 6 |
| Angiotensin-converting enzyme inhibitors (e.g., captopril, enalapril, lisinopril) | Serum potassium level | 6 | 3 | 6 | 6 |
| Amiodarone | Serum liver function tests | 6 | 6 | 3 | 6 |
| Amiodarone | Thyroid-stimulating hormone level | 6 | 6 | 6 | 6 |
| Antidiabetic medications (e.g., metformin, glyburide, insulin) | Fasting serum glucose or glycated hemoglobin level | 6 | 6 | 6 | 6 |
| Antipsychotic medications (e.g., haloperidol, risperidone, quetiapine) | Fasting serum glucose or glycated hemoglobin level | 6 | 6 | 6 | 6 |
| Antipsychotic medications (e.g., haloperidol, risperidone, quetiapine) | Serum lipid panel | 6 | 12 | 6 | 6 |
| Carbamazepine | Trough serum carbamazepine level | 6 | 6 | 6 | 6 |
| Cyclosporine | Trough serum cyclosporine level | 3 | 3 | 3 | 3 |
| Digoxin | Serum blood urea nitrogen and serum creatinine level | 3 | 6 | 6 | 6 |
| Digoxin | Trough serum digoxin level | 6 | 6 | 6 | 6 |
| Disopyramide | Trough serum disopyramide level | 12 | 6 | 3 | No agreement about interval |
| Diuretics (e.g., furosemide, hydrochlorothiazide, spironolactone) | Serum sodium and potassium level | 3 | 3 | 3 | 3 |
| Erythropoiesis-stimulating agents (i.e., epoetin alfa, darbepoetin alfa) | Complete blood count | 1 | 1 | 1 | 1 |
| Fibrates (e.g., fenofibrate, clofibrate) | Complete blood count | 6 | 6 | 6 | 6 |
| Fibrates (e.g., fenofibrate, clofibrate) | Serum liver function tests | 6 | 6 | 6 | 6 |
| Glucocorticoids, oral | Fasting serum glucose or glycated hemoglobin level | 6 | 3 | 3 | 3 |
| Lithium | Trough serum lithium level | 3 | 3 | 3 | 3 |
| Metformin | Serum blood urea nitrogen and creatinine level | 6 | 6 | 3 | 6 |
| Niacin | Fasting serum glucose or glycated hemoglobin level | 6 | 6 | 6 | 6 |
| Niacin | Serum liver function tests | 6 | 6 | 6 | 6 |
| Phenobarbital | Trough serum phenobarbital level | 6 | 6 | 6 | 6 |
| Phenytoin | Trough serum phenytoin level | 3 | 6 | 3 | 3 |
| Primidone | Trough serum primidone level | 6 | 6 | 3 | 6 |
| Procainamide | Trough serum procainamide or N-acetylprocainamide level | 6 | 6 | 6 | 6 |
| Quinidine | Trough serum quinidine level | 6 | 6 | 6 | 6 |
| Salicylate (e.g., aspirin >1,200 mg/day, salsalate, choline magnesium trisalicylate) | Trough serum salicylate level | 6 | 6 | 6 | 6 |
| Statins (e.g., lovastatin, simvastatin) | Serum liver function tests | 6 | 6 | 6 | 6 |
| Theophylline | Trough serum theophylline level | 3 | 3 | 6 | 3 |
| Thyroid medications (e.g., levothyroxine, triiodothyronine, propylthiouracil) | Thyroid-stimulating hormone level | 12 | 6 | 6 | 6 |
| Ticlopidine | Complete blood count with neutrophil count | 6 | 3 | 3 | 3 |
| Tricyclic antidepressants (e.g., amitriptyline, desipramine, imipramine) | Trough serum tricyclic antidepressant level | 12 | 12 | 6 | 12 |
| Valproic acid | Trough serum valproic acid level | 3 | 6 | 3 | 3 |
| Warfarin | International normalization ratio | 1 | 1 | 1 | 1 |
*
Where agreement is defined as having two or more of the three professional groups selecting the same monitoring interval.