As a result, serum lithium levels increase secondary to enhanced reabsorption.If coadministration is necessary, the dosage of lithium should be reduced by 50 percent when a diuretic or an NSAID is added. Interactions of warfarin with drugs and food. Although potentiation of warfarin by lovastatin has been reported in at least 10 patients, controlled trials in large numbers of patients are needed to discern the clinical importance of this effect.Over the past 15 years, selective serotonin reuptake inhibitors (SSRIs) have become the most commonly used antidepressant drugs. Laupacis A, Jarjoura D, Precipitant drugs modify the object drug's absorption, distribution, metabolism, excretion or actual clinical effect. Gunstensen J, HTB. Conner SL. Oral contraceptive failure rates and oral antibiotics. Vancouver, Wash.: Applied Therapeutics, 1997;7–8,309,368–9,415–6.Hylek EM, Quinolonecation interactions: a review. A WARNING ABOUT MILK THISTLE AND DRUGS The seeds of the milk thistle plant are commonly used to protect the liver from damage caused by hepatitis viruses as well as alcohol and other substances. If either combination is used, patients should be alert for muscle pain, tenderness or weakness. Paterson A. To see the full article, log in or purchase access.INR = International Normalized Ratio; NSAID = nonsteroidal anti-inflammatory drug; HMG-CoA = 3-hydroxy-3-methylglutaryl–coenzyme A reductase inhibitor; SSRI = selective serotonin reuptake inhibitorINR = International Normalized Ratio; NSAID = nonsteroidal anti-inflammatory drug; HMG-CoA = 3-hydroxy-3-methylglutaryl–coenzyme A reductase inhibitor; SSRI = selective serotonin reuptake inhibitor*—Combining an agent that inhibits cytochrome P450 metabolism with a substrate of cytochrome P450 may potentiate the pharmacologic effects of the substrate through inhibition of hepatic metabolism*—Combining an agent that inhibits cytochrome P450 metabolism with a substrate of cytochrome P450 may potentiate the pharmacologic effects of the substrate through inhibition of hepatic metabolismComplete database for drug interactions as well as clinically useful drug information; updated quarterlyHansten and Horn's Drug Interactions Analysis and Management (manual)Easy-to-use index that categorizes a drug interaction by clinical significance, along with a concise reference monograph discussing the interaction; updated quarterlyHandbook of Adverse Drug Interactions (manual); Adverse Drug Interactions Program (software, Internet)Software searches for interactions between two and up to 25 drugsDrug Interactions Analysis and Management (loose-leaf or bound manual); Drug Interaction Facts (loose-leaf or bound manual with software)Information about drug-drug and drug-food interactions in a quick reference format, along with descriptive monographs of drug interactions selected on the basis of their potential to alter patient outcomes; updated quarterlyComplete database for drug interactions as well as clinically useful drug information; updated quarterlyHansten and Horn's Drug Interactions Analysis and Management (manual)Easy-to-use index that categorizes a drug interaction by clinical significance, along with a concise reference monograph discussing the interaction; updated quarterlyHandbook of Adverse Drug Interactions (manual); Adverse Drug Interactions Program (software, Internet)Software searches for interactions between two and up to 25 drugsDrug Interactions Analysis and Management (loose-leaf or bound manual); Drug Interaction Facts (loose-leaf or bound manual with software)Information about drug-drug and drug-food interactions in a quick reference format, along with descriptive monographs of drug interactions selected on the basis of their potential to alter patient outcomes; updated quarterlyAddress correspondence to Paul W. Ament, Pharm.D., Clinical Pharmacy Services, Latrobe Area Hospital, 121 W. 2nd Ave., Latrobe, PA 15650.
If combination therapy is necessary, have the patient take an oral contraceptive pill with a higher estrogen content (>35 μg of ethinyl estradiol) or recommend alternative method of contraception.Avoid if possible. If combination therapy is necessary, recommend use of alternative contraceptive method during cycle.Have the patient take an oral contraceptive pill with a higher estrogen content or recommend alternative method of contraception.Prolongation of QT interval along with arrhythmias secondary to inhibited cisapride metabolismAvoid. Cisapride has been associated with prolongation of the QT interval, torsades de pointes, syncope, cardiac arrest and sudden death.The primary agents contraindicated for use with cisapride are certain macrolide antibiotics (erythromycin and clarithromycin), certain antifungal agents (fluconazole, itraconazole [Sporanox] and ketoconazole [Nizoral]), one antidepressant drug (nefazodone [Serzone]) and certain protease inhibitors (indinavir [Crixivan] and ritonavir [Norvir]).Most data on cisapride interactions are derived from case reports. Singer DE. All SSRIs except paroxetine (Paxil) have pharmacologically active metabolites.The most common interactions with SSRIs result from an inhibitory effect of the SSRI on the cytochrome P450 2D6 pathway, although variability in this inhibition exists.