DrugInteractions





Coenzyme Q10 has potential to inhibit the effects of warfarin (Coumadin), a potent anticoagulant, by reducing the INR. https://en.wikipedia.org/wiki/Coenzyme_Q10

AKI: 
1.TMP/SMX inhibits cr secretion in the distal nephron. 
2. combining nsaid w/ ACEi can be a bad choice, esp if pt depends on NSAIDs for mobility.
3. low dose trial of COX-2 can be attempted while monitoring RF.

HTN:
1. nsaids cause Na and H20 retention so low dose diuretic could be a good choice if on nsaids.

Levaquin - watch for QT changes and changes in warfarin metabolism: PT INR etc. changes

Bactrim - trimethoprim - a K-sparing diuretic, also causes bone marrow suppression (tag: hyperkalemia pancytopenia )

Loperamide Toxicity - prolonged QT ?
- decreased respiratory drive, snoring respiration, LOC, sz
- urinary incontinence
- vTac - shocked w/ 200J w/ return to NSR
- EP recommended lidocaine
- isoproterenol 1µg, then ggt to raise HR to goal 90-100 and help shorten QTc


Neutropenia has a 2% incidence rate associated with the use of Valsartan, also assoc w/ some nsaids and synthetic pennisillins. - as per Dr. Bismayer (6.7.15)

Loss of BP control may occur when an SSRI is started on a person taking clonidine. Wolters Kluwer Co.

Women also secrete less gastric acid than men, so they may need to drink an acidic beverage to aid in absorption of medications that require an acidic environment, such as ketoconazole. Women usually have lower BMIs than men, and may need smaller loading or bolus dosages of medications to avoid unnecessary adverse reactions. Women typically have higher fat stores than men, so lipophilic drugs such as benzodiazepines and neuromuscular blockers have a longer duration of action. Women also have lower glomerular filtration rates than men, resulting in slower clearance of medications that are eliminated renally, such as digoxin and methotrexate.  REF

When switching from an SSRI to an MAO inhibitor, a washout period of five half-lives of the SSRI is recommended. REF

Ataxia is the sign of toxicity in a phenytoin (Dilantin) patient. REF Sreen at each visit !

Tramadol should be used with caution in patients with a history of seizure disorder or those taking other medications that lower seizure thresholds. REF https://nf.aafp.org/Assessment/Take/728/c/eb1cf646-789c-47e5-8138-d2969fd3174f

Cipro decreases theophylline clearance - elevation of which causes N/V.

Grapefruit juice increases concentrations of statins (esp simvastatin and lovastatin) and nifedipine.

Clarithromycin is the king of drug interactions and markedly downgrades P450. MedStudy-Rheum.
- Majority of deaths due to colchicine interactions were 2/2 Clarithromycin.

Ginko interacts with what to cause what ? (REF)

CYP450 inhibitors and inducers - name those in this Q. (REF)

BBs and clonidine worsen depression. REF

Thiazide improve osteoporosis. REF

Warfarin metabolization (in liver) is decreased by Amiodarone.

Dig toxicity caused by: amio, quinidine, spironolactone, verapamil

ACE-Is decr AII which decr GRF which increase Cr !

Calcitonin - weak anti-resorptive, nasal spray, reduces risk of vertebral compression fractures in severe cases of osteoporosis, 'tones down calcium in the blood'.

Calcitriol - used to tx hypoclacemia in early postop period, the hormonally active form of Vit D
-    increases Ca2+ uptake from gut
-    increases Ca2+ release from bone
-    decreases Ca2+ in urine
Alendronate - DOC in Paget's ds
Raloxifen - DEXA -2.7 and high risk for breast cancer

Paricalcitrol (Zemplar) - prevents secondary hyperthyroidism by mimicing Vit D2 (1,25 dihydroxyergocalciferol)

Sevelamer (Renagel) - binds phospate and decreases its absorption.

Prolonged QT - hypocalcemia, erythromycin, TCAs.
Ziprasidone is a second-generation antipsychotic used in the treatment of schizophrenia. These drugs cause QT-interval prolongation, which can in turn lead to torsades de pointes and sudden cardiac death. This risk is further increased when these drugs are combined with certain antibiotics (e.g., clarithromycin), antiarrhythmics (class I and III), and TCAs.

AV Nodal block - Lyme ds

Cisapride - increases myenteric plexus Ach release - associated with arrhythmia. why ?

Can't use greater than 40 mg Zocor wth Norvasc 10 mg or some such - look it up.

Nicotinic acid is problematic in diabetics, as it tends to cause deterioration in glucose control.

Lithium elevates PTH. What is the side effect of this ? REF

Vitamin K inhibitors: phenytoin, phenobarbital, rifampin, isoniazid, warfarin.

Amp B - Causes renal insufficiency with metabolic acidosis 2/2 distal tubular acidification defect with hyperchloremia, a normal AG and high urine pH.



Comments