Real Life Pharmacology - Pharmacology Education For Health Care Professionals

Lactulose is an osmotic laxative but it is rarely used for this purpose. I discuss lactulose pharmacology in this episode. Elevated ammonia levels are an issue in hepatic encephalopathy. Lactulose can help manage this issue. Lactulose is dosed to 2-3 soft stools per day when used to reduce ammonia levels. Lactulose can increase the effect of warfarin and raise INR; I discuss this further on this episode.

On this episode, I discuss ticagrelor pharmacology, adverse effects, and important drug interactions. Ticagrelor has a warning with regards to the use of aspirin. Higher doses of aspirin can impair the effectiveness of ticagrelor and I discuss this further on this episode. Bleeding is the major adverse effect from ticagrelor and naturally, hematocrit and hemoglobin are important monitoring parameters. I discuss CYP3A4 drug interactions on this episode and how it may affect ticagrelor.

On this podcast episode, I discuss lurasidone pharmacology, adverse effects, and drug interactions. CYP3A4 is an important enzyme in the breakdown of lurasidone. I discuss this further on this episode. Lurasidone is best taken with food as this enhances absorption and helps improve drug concentrations. Lurasidone tends to have a lower risk for metabolic syndrome compared to other antipsychotics which is a nice advantage.

Isavuconazole is an azole antifungal that can be used for various fungal infections. In this episode, I discuss isavuconazole pharmacology, adverse effect, drug interactions, and pharmacokinetics. Isavuconazole is interestingly associated with QT shortening which is different from most azole antifungals that cause QT prolongation. Oral bioavailability of isavuconazole is nearly 100% so dose conversions between IV and oral are typically not difficult to navigate.

On this episode, I cover ethinyl estradiol pharmacology. This is a common component of oral contraceptives. You have to check out this free resource (with free account) from Pyrls.com/rlp which lists all the different combinations and brand names. All it takes is to simply sign up for a free account here. Ethinyl estradiol dosing can vary. Breakthrough bleeding is a major reason why a patient might prefer a higher dose. Blood clot risk is a real problem with ethinyl estradiol. There are numerous situations where we should avoid ethinyl estradiol and I cover them in this episode. Be careful with enzyme inducers like carbamazepine, rifampin, etc. as they can reduce the concentrations of oral contraceptives

On this episode, I discuss olmesartan (Benicar) pharmacology, adverse effects, drug interactions, and pharmacokinetics. Olmesartan can cause a unique GI adverse effect called enteropathy. I discuss this on this podcast episode. Important monitoring parameters for olmesartan include potassium, renal function, and blood pressure. Olmesartan has a longer half-life than losartan. I discuss how this might be advantageous in clinical practice.

On this episode, I discuss desvenlafaxine pharmacology, adverse effects, pharmacokinetics, and drug interactions. Desvenlafaxine is a serotonin and norepinephrine reuptake inhibitor that can be used for depression. Renal elimination is an important method of deactivation of desvenlafaxine. Dose adjustments may be recommended as renal function drops below 50 mls/min. Withdrawal syndrome due is a risk with desvenlafaxine as it has a significantly short half-life.

Pramipexole (Mirapex) is a dopamine agonist that can be used in Parkinson’s disease and Restless Legs Syndrome. Dopamine agonists like pramipexole can worsen psychiatric symptoms in some patients by causing hallucinations, and obsessive/compulsive symptoms. Nausea, vomiting, hypotension, and fatigue are the most common adverse effects of pramipexole. Pramipexole is primarily eliminated through the urine. I discuss how this matters clinically in greater detail in this podcast episode.

I mentioned prednisolone to prednisone conversion in this podcast. Please go check out Pyrls.com for a free steroid conversion downloadable PDF with a free account! On this episode, I discuss prednisolone (Orapred, Pediapred) pharmacology, adverse effects, practice pearls, and drug interactions. Prednisolone is a systemic corticosteroid that can cause insomnia, elevations in blood sugars, and numerous effects if used long-term. CYP3A4 is an important enzyme in the breakdown of prednisolone. Inhibitors or inducers may raise or lower drug levels respectively.

On this episode, I discuss bisoprolol (Zebeta) pharmacology, adverse effects, drug interactions, and other important clinical pearls. Bisoprolol is a beta-1 selective antagonist that can be used for atrial fibrillation, angina, and other cardiovascular indications. It is important to remember that bisoprolol and other beta-blockers are not considered first-line agents for hypertension alone. Beta-receptor selectivity does start to disappear with bisoprolol as you get to higher dosages. I discuss this further in the podcast.

Lansoprazole is a proton pump inhibitor that can be commonly used for GERD, PUD, and GI prophylaxis. Lansoprazole can inhibit CYP2C19 which can cause concentrations of drugs like escitalopram and citalopram to rise. Hypomagnesemia, low B12, osteoporosis, and an increase in C. Diff risk are potential complications with longer-term PPI use. PPIs like lansoprazole are best given 30-60 minutes before meals. This is something that patients often forget. I discuss important drug interactions on the podcast, be sure to check out my latest project which is a 200+ page book on managing drug interactions in primary care. Be sure to check out our free Top 200 study guide – a 31-page PDF that is yours for FREE!

Ropinirole (Requip) is a dopamine agonist that can be used in Parkinson's disease and Restless Legs Syndrome. Dopamine agonists like ropinirole can worsen psychiatric symptoms in some patients by causing hallucinations, and obsessive/compulsive symptoms. Nausea, vomiting, hypotension, and fatigue are the most common adverse effects of ropinirole. Ropinirole has drug interactions with antipsychotics and CYP1A2 inhibitors. I discuss these in greater detail in this podcast episode.

On this episode of the podcast, I cover budesonide (Pulmicort) pharmacology. Our sponsor (Pyrls.com/rlp) for this episode is providing a FREE PDF of their inhaled corticosteroid categorizations chart (i.e. low/medium/high dose ICS) when you sign up for a free account! The onset of action of inhaled budesonide is several hours up to a few days. Patient education is critical to ensure that patients stick with its use. Budesonide does have a nebulized formulation that is often used in pediatrics and geriatrics. There aren't a ton of critical drug interactions, but you should think about medications that inhibit CYP3A4 and may have additive immunosuppressive effects.

Canagliflozin is an SGLT2 inhibitor. I discuss the pharmacology, dosing, adverse effects, and drug interactions of this medication. Canagliflozin reduces blood sugar, by facilitating its exit through the urine. This can increase the risk of genitourinary infections. A diuresis type effect can happen due to canagliflozin and this effect may be exacerbated by the use of thiazide and loop diuretics. Hyperkalemia has been reported with the use of canagliflozin; the risk for this is increased with the use of medications like ACE inhibitors, ARBs, and aldosterone antagonists.

Cabergoline is a dopamine agonist. I discuss the pharmacology, adverse effects, and drug interactions in this podcast episode. Be on the lookout for drugs that could oppose the effects of cabergoline such as antipsychotics and metoclopramide. Cabergoline can be used for hyperprolactinemia management and may cause adverse effects like hypotension and GI upset. Cabergoline has a very long half-life so it is most often only dosed 1-2 times per week.

In this episode, I discuss venlafaxine pharmacology, adverse effect, dose conversion of IR to ER, and drug interactions. Venlafaxine is notorious for producing withdrawal symptoms when discontinued abruptly. I discuss these in detail on the podcast. How significant is the interaction of venlafaxine with antiplatelet agents? I discuss that in this episode. The onset of action is a critical education point that patients must be aware of as it takes some time for venlafaxine to work.

On this episode I discuss chlorthalidone pharmacology, adverse effects, and recent literature regarding cardiovascular disease reduction. Our friends at Pyrls.com are offering a free diagram of the nephron including the mechanism of action AND a summary of diuretic effects that I discussed on the podcast - Go sign up and get these for free and support this awesome sponsor! Chlorthalidone is a thiazide diuretic that uniquely raises blood calcium levels compared to loop diuretics which lower calcium levels. There was a recent piece of literature (2020) comparing chlorthalidone versus hydrochlorothiazide. It found that chlorthalidone was no more effective than HCTZ. Remember that chlorthalidone can raise uric acid and increase the risk of gout flares.

On this episode, I discuss verapamil pharmacology, adverse effects, and important drug interactions. There are numerous drug interactions to be aware of with verapamil as it inhibits the enzyme CYP3A4. Verapamil is a calcium channel blocker (non-dihydropyridine) that blocks calcium channels in the heart and vessels. In addition to hypotension and bradycardia, verapamil can cause constipation which may be more prominent in our geriatric patients.

In this episode, I cover salmeterol (Serevent) pharmacology, adverse effects, drug interactions and special warnings with this medication. Salmeterol is a long acting beta agonist that can be used in combination with inhaled corticosteroids for management of asthma. Salmeterol can be used as monotherapy in COPD and should not be used as monotherapy in asthma. Elevations in pulse and blood pressure can happen with a beta agonist like salmeterol.

On this episode, I discuss esomeprazole (Nexium) pharmacology, adverse effects, tapering, kinetics, and drug interactions. I spend a good amount of time discussing the esomeprazole and clopidogrel interaction in this podcast episode. Esomeprazole inhibits CYP2C19. This can cause an increase in citalopram concentrations and raise the potential for QTc prolongation. It is critical to reassess the length of therapy and the dose of PPIs like esomeprazole.