Real Life Pharmacology - Pharmacology Education For Health Care Professionals

Vilazodone (brand name Viibryd) is an antidepressant with a unique pharmacologic profile compared to most other agents in the SSRI class. While not a first-line choice for every patient, understanding its mechanism, adverse effects, and interaction profile is essential for optimizing therapy and preventing downstream prescribing problems. Mechanism of ActionVilazodone is classified as a selective serotonin reuptake inhibitor (SSRI) and a partial agonist at the 5-HT1A receptor. The SSRI activity increases synaptic serotonin by blocking the serotonin transporter, while partial agonism at 5-HT1A receptors may contribute to antidepressant effects and potentially reduce certain SSRI-associated adverse effects (though clinical evidence for this benefit is mixed). Adverse Effects GI effects – diarrhea, nausea, and vomiting are frequent early in therapy. Taking the medication with food can help minimize these. Insomnia – often dose-related; morning dosing may help. Sexual dysfunction – may be slightly

Solifenacin is a bladder antimuscarinic medication most commonly used for overactive bladder (OAB) with symptoms of urinary frequency, urgency, and urge incontinence. Like other agents in its class, understanding the pharmacology can help anticipate potential side effects, drug interactions, and downstream prescribing problems. Mechanism of Action Solifenacin selectively blocks muscarinic M3 receptors in the bladder detrusor muscle. Inhibiting these receptors reduces involuntary bladder contractions, increases bladder capacity, and delays the urge to void. While M3 selectivity may theoretically reduce side effects compared to nonselective antimuscarinics, in clinical practice, many anticholinergic effects still occur. Adverse Effects Because muscarinic receptors are present throughout the body, solifenacin can lead to a range of anticholinergic adverse effects: Dry mouth – among the most common, can be significant enough to cause dental issues with long-term use. Constipation – especially p

In this episode, we break down itraconazole—a potent antifungal with a lot of baggage. If you’re a pharmacist, clinician, or student who needs to understand how this drug works and why it can be tricky to use, this episode is for you. We start with the basics. Itraconazole blocks 14α-demethylase, an enzyme fungi need to make their cell membranes. That disruption kills or slows the fungus. It works against tough bugs like Aspergillus, Histoplasma, and Blastomyces, plus common skin infections. Side effects? Nausea, liver enzyme elevations, and more seriously, heart failure. Yes, itraconazole has a black box warning for worsening or causing congestive heart failure. If your patient has heart issues, think twice. Drug interactions are everywhere. Itraconazole is a strong CYP3A4 inhibitor. It can raise levels of drugs like statins, benzos, calcium channel blockers, and immunosuppressants—sometimes to dangerous levels. Don’t co-prescribe without checking.

In this episode of our pharmacology podcast, we take a deep dive into the pharmacology of levomilnacipran (Fetzima), a unique serotonin-norepinephrine reuptake inhibitor (SNRI) approved for the treatment of major depressive disorder (MDD) in adults. Designed for pharmacy students, clinicians, and anyone interested in psychopharmacology, this episode breaks down what makes levomilnacipran different from other antidepressants and how to use it effectively in clinical practice. We explore levomilnacipran's mechanism of action, which features a greater affinity for norepinephrine reuptake inhibition compared to serotonin—an uncommon trait among SNRIs. This pharmacologic profile gives it a distinctive effect on energy, motivation, and physical symptoms of depression. Listeners will also learn about its pharmacokinetics, including once-daily dosing, renal elimination, and metabolism via the CYP3A4 pathway—making drug interactions an important consideration. The episode also covers levomilnacipran side effects

Asenapine is an atypical antipsychotic that acts as an antagonist at multiple receptors, including dopamine D2 and serotonin 5-HT2A, contributing to its antipsychotic and mood-stabilizing effects. Adverse effects of asenapine include somnolence, dizziness, and extrapyramidal symptoms. Because asenapine is significantly metabolized by CYP1A2, inhibitors or inducers of these enzymes can affect its plasma concentrations. Co-administration with other CNS depressants may increase the risk of sedation and impaired cognitive or motor function. Asenapine can prolong the QT interval, so caution is advised when used with other medications that affect cardiac conduction.

Loxapine is a first-generation (typical) antipsychotic with dopamine D2 receptor antagonism as its primary mechanism, though it also has affinity for serotonin 5-HT2A receptors, making its pharmacology somewhat atypical. Loxapine is available in multiple formulations, including oral capsules and an inhalation powder, the latter approved specifically for acute agitation in patients with schizophrenia or bipolar I disorder. Sedation and extrapyramidal symptoms (EPS), including dystonia, akathisia, and parkinsonism, are common adverse effects due to its potent dopamine blockade in the nigrostriatal pathway. Orthostatic hypotension can occur with loxapine due to its alpha-1 adrenergic blockade, requiring monitoring in elderly patients or those on antihypertensives.

Ketoconazole is an imidazole antifungal that works by inhibiting fungal cytochrome P450 14α-demethylase, an enzyme essential for ergosterol synthesis, which disrupts fungal cell membrane integrity. Common adverse effects of ketoconazole include nausea, vomiting, abdominal pain, and elevated liver enzymes, with hepatotoxicity being a notable concern. Ketoconazole carries a boxed warning for severe hepatotoxicity, including cases of liver failure and death, and should not be used as a first-line treatment for fungal infections when other safer antifungals are available. Another boxed warning highlights ketoconazole’s potential to prolong the QT interval, increasing the risk for life-threatening ventricular arrhythmias such as torsades de pointes. Ketoconazole is a strong inhibitor of CYP3A4 and can cause significant drug interactions by increasing serum concentrations of medications metabolized by this pathway, including statins, certain benzodiazepines, and some antiarrhythmic.

NSAIDs can reduce the effectiveness of antihypertensive medications such as ACE inhibitors, ARBs, beta-blockers, and diuretics by promoting sodium and water retention and decreasing renal blood flow. Combining NSAIDs with anticoagulants or antiplatelet agents like warfarin or aspirin significantly increases the risk of gastrointestinal bleeding, due to additive effects on platelet inhibition and mucosal irritation. NSAIDs can elevate lithium levels and increase the risk of toxicity, as they reduce renal clearance of lithium by decreasing renal perfusion. Co-administration of NSAIDs with methotrexate can impair methotrexate elimination, leading to elevated levels and potential toxicity, especially at high methotrexate doses. When NSAIDs are used with corticosteroids, the risk of gastrointestinal ulcers and bleeding is greatly amplified due to synergistic impairment of gastric mucosal protection.

Lotrisone is a topical cream that contains a combination of clotrimazole, an antifungal, and betamethasone dipropionate, a corticosteroid. It is used to treat fungal skin infections such as athlete’s foot, jock itch, and ringworm that also involve inflammation or itching. Clotrimazole works by disrupting the fungal cell membrane, while betamethasone reduces redness, swelling, and itching. Lotrisone should not be used on the face, groin, or underarms for extended periods due to the risk of skin thinning and other steroid-related side effects.

Fluphenazine is a high-potency typical antipsychotic that primarily acts as a dopamine D2 receptor antagonist in the mesolimbic pathway, reducing positive symptoms of schizophrenia. Extrapyramidal symptoms (EPS), such as dystonia, akathisia, and parkinsonism, are common due to potent D2 blockade in the nigrostriatal pathway. Neuroleptic malignant syndrome (NMS), though rare, is a life-threatening adverse effect characterized by rigidity, hyperthermia, altered mental status, and autonomic instability. CYP2D6 inhibitors (e.g., fluoxetine, paroxetine) can increase fluphenazine plasma concentrations, potentially raising the risk of toxicity and side effects. Concomitant use of fluphenazine with CNS depressants (e.g., alcohol, benzodiazepines) can enhance sedation and respiratory depression.

On this podcast episode, I discuss quinapril pharmacology, adverse effects, drug interactions, pharmacokinetics, and much more. Quinapril is a prodrug that is converted in the liver to its active metabolite, quinaprilat, which inhibits ACE, leading to decreased formation of angiotensin II and reduced aldosterone secretion. Hyperkalemia can occur with quinapril use due to decreased aldosterone, leading to potassium retention—especially in patients with renal impairment. Concomitant use of potassium-sparing diuretics or potassium supplements with quinapril increases the risk of hyperkalemia. NSAIDs may reduce the antihypertensive effect of quinapril and increase the risk of nephrotoxicity, especially in patients with preexisting renal dysfunction.

Nifedipine is a dihydropyridine calcium channel blocker that selectively inhibits L-type calcium channels in vascular smooth muscle, leading to vasodilation and reduced peripheral vascular resistance. The extended-release formulation of nifedipine provides more stable plasma concentrations and is preferred for chronic management of hypertension and angina. Common adverse effects include headache, flushing, peripheral edema, and dizziness, all related to its vasodilatory action. Nifedipine undergoes extensive first-pass metabolism in the liver, primarily via CYP3A4 enzymes, which significantly influences its bioavailability and potential drug interactions. CYP3A4 inhibitors (e.g., ketoconazole, erythromycin, grapefruit juice) can increase plasma levels of nifedipine, raising the risk of hypotension and adverse effects.

On this podcast episode, I discuss Clotrimazole pharmacology, adverse effects, indications, administration, and much more. Clotrimazole is an imidazole antifungal that exerts its pharmacological effect by inhibiting the synthesis of ergosterol, an essential component of fungal cell membranes. This inhibition compromises membrane integrity, leading to leakage of cellular contents and ultimately fungal cell death. Clotrimazole is primarily used topically due to poor systemic absorption when administered via the skin or mucous membranes, which limits systemic side effects. When clotrimazole is used intravaginally or orally in lozenge form, localized concentrations are sufficient to treat mucocutaneous infections without significant systemic exposure. Pay attention when clotrimazole is used frequently to treat Candida infections as corticosteroids, immunosuppression, and antibiotics may increase the risk of this type of infection.

Irbesartan is an angiotensin II receptor blocker (ARB) used primarily for the management of hypertension and diabetic nephropathy in type 2 diabetes. It selectively inhibits the binding of angiotensin II to the AT1 receptor found in vascular smooth muscle and the adrenal gland. This blockade results in vasodilation, reduced aldosterone secretion, decreased sodium and water retention, and ultimately lower blood pressure. Irbesartan is administered orally, with a typical starting dose of 150 mg once daily, which may be increased to 300 mg depending on the patient’s clinical response and tolerability. Adverse effects of irbesartan are generally mild but can include hyperkalemia and dizziness. Hypotension may occur, especially in volume-depleted individuals or those on diuretics. Routine monitoring of renal function and serum potassium is recommended, especially in patients with underlying kidney disease or those taking potassium-sparing agents or supplements. Irbesartan is contraindicated in p

On this episode, I discuss benzonatate pharmacology, adverse reactions, and much more. Tessalon Pearls (benzonatate) are a non-narcotic antitussive commonly prescribed to relieve dry, non-productive coughs. Benzonatate acts by numbing stretch receptors in the respiratory tract, lungs, and pleura, which helps suppress the cough reflex at its source. Unlike opioid-based cough suppressants, it doesn’t work in the brain’s cough center. The usual adult dose is 100 to 200 mg taken orally three times a day as needed, with a maximum daily dose of 600 mg. One of the most critical points is that the capsules must be swallowed whole. Chewing, sucking, or crushing them can cause numbness in the mouth and throat, leading to a risk of choking or aspiration. There are no major drug interactions associated with benzonatate.

On this episode of the Real Life Pharmacology podcast, I discuss Miralax (polyethylene glycol) pharmacology, adverse effects, and much more. MiraLAX is an osmotic laxative commonly used to treat occasional constipation by retaining water in the stool to increase stool frequency and soften consistency. The standard adult dose of MiraLAX is 17 grams (approximately one heaping tablespoon) dissolved in 4 to 8 ounces of liquid once daily. Electrolyte imbalances are rare but possible with prolonged or excessive use of Miralax, particularly in elderly or renal-impaired patients. Advise patients to maintain adequate hydration while using MiraLAX to support its mechanism and reduce side effects.

Today’s sponsor is Freed AI! Freed’s AI medical scribe listens, transcribes, and writes notes for you. Over 15,000 healthcare professionals use Freed and you should too! Learn more here! On this episode of the Real Life Pharmacology Podcast, we cover minoxidil pharmacology, adverse effects, drug interactions, and much more. Minoxidil is a potent arterial vasodilator used in the treatment of hypertension and androgenetic alopecia. The route of administration greatly impacts the drug’s safety profile. Oral minoxidil is typically reserved for refractory hypertension due to its strong systemic effects and associated risks. Topical formulations (2% or 5%) are widely used for hair regrowth, offering local benefits with minimal systemic absorption. Systemic minoxidil can result in fluid retention, tachycardia, and even pericardial effusion, often requiring co-administration with a diuretic and beta-blocker.

Today’s sponsor is Freed AI! Freed’s AI medical scribe listens, transcribes, and writes notes for you. Over 15,000 healthcare professionals use Freed and you should too! Learn more here! Prednisone is a commonly used medication for its antiinflammatory and immunosuppressive action. On this episode I discuss prednisone pharmacology, ADRs, and much more. In the episode, I discuss how prednisone affects the HPA system in the body. Cortisol production can be greatly impacted by long term use of prednisone. GI adverse effects can be problematic with oral prednisone which is why we often give this medication with food or milk. Hyperglycemia is a complication from the use of prednisone. I've commonly seen blood sugar spike by 50-100+ mg/dL due to this medication. Osteoporosis is a long term risk with the use of prednisone. Prednisone can also impact the benefits of vaccination. I discuss this in greater depth in the drug interactions portion of the podcast.

Today’s sponsor is Freed AI! Freed’s AI medical scribe listens, transcribes, and writes notes for you. Over 15,000 healthcare professionals use Freed and you should too! Learn more here! On this episode of the Real Life Pharmacology Podcast, I cover linagliptin pharmacology, adverse effects, drug interactions, and much more. Linagliptin is a DPP-4 inhibitor used to help control blood sugar levels in adults with type 2 diabetes. It works by increasing the levels of incretin hormones, which stimulate insulin release and decrease glucagon levels in the blood. Linagliptin is usually taken once daily and can be used alone or in combination with other diabetes medications. Unlike some other diabetes drugs, linagliptin does not usually cause weight gain or low blood sugar (hypoglycemia) when used alone. Linagliptin should not be used with GLP-1 agonists as it works on a similar pathway as that medication class.

Meclizine is classified as a first-generation antihistamine. I discuss meclizine pharmacology, adverse effects, drug interactions, and much more. Meclizine is included on the Beers list due to its highly anticholinergic activity. Anticholinergic effects include constipation, dry eyes, dry mouth, urinary retention, and confusion. Sedation is an important adverse effect of meclizine. This adverse effect can be increased when used with other sedating medications such as opioids and benzodiazepines. Meclizine is primarily used for vertigo and motion sickness in clinical practice. The usual starting dose ranges between 12.5 to 25 mg. Meclizine is partially broken down by CYP2D6 so medications like bupropion can inhibit the breakdown of meclizine and lead to higher concentrations.