Pharm Flashcards
A BEAM
Most beta blockers whose names start with A-M are beta-1-selective. In addition, a mnemonic to remember some of the more common beta-1 blockers is A BEAM (acebutolol, betaxolol, esmolol, atenolol, and metoprolol).
Epinephrine is an agonist of what receptors?
alpha-1 alpha-2 beta-1 beta-2
Phenazopyridine
Phenazopyridine (choice E) is an analgesic with special properties that can provide pain relief in the genitourinary tract.
Norepinephrine is an agonist of what receptors?
alpha-1 alpha-2 beta-1
Cyclosporine
Cyclosporine is a fungus-derived polypeptide that complexes with cyclophilin and inhibits calcineurin.
Inhibition of calcineurin decreases production of IL-2.
Grapefruit juice dramatically increases the bioavailability of cyclosporine by inhibiting CYP3A, the same enzyme system that metabolizes cyclosporine.
Cyclosporine is indicated for the prevention of renal transplant rejection and the treatment of rheumatoid arthritis, and may be effective in patients with systemic lupus erythematosus, polymyositis, dermatomyositis, and granulomatosis with polyangiitis (Wegener’s).
Diltiazem
Diltiazem, an example of a L-type calcium channel blocker, acts by inhibiting calcium ion influx (choice C) into vascular smooth muscle and myocardium, decreasing peripheral vascular resistance, dilating coronary arteries, and prolonging the AV node refractory period. Diltiazem is used for hypertension, chronic stable angina, and supraventricular tachycardias. Side effects include hypotension and AV block.
Acetazolamide
Acetazolamide, a carbonic anhydrase inhibitor, can cause hypokalemia, metabolic acidosis, and an alkaline urine.
Torticollis is an example of:
Acute dystonic reaction from treatment with high potency D2 receptor agonists such as haloperidol; involuntary muscle contractions
Pavlizumab
Respiratory syncytial virus (RSV) can cause serious lower respiratory tract infections in infants.
Prophylaxis is with palivizumab, which is a monoclonal antibody directed against the fusion protein of RSV. This prevents infection of the host cell.
Give the equation for half life.
The volume of distribution (Vd) is a hypothetical volume of body fluid that would be required to dissolve the total amount of drug at the same concentration that is found in the blood.
The formula t1/2 = (0.7 x Vd)/CL can be used to solve for volume of distribution if the half-life (t1/2) and clearance (CL) are known.
Drugs to increase contractility
↑ contractility: digoxin, beta agonists
MOA Sirolimus
Sirolimus inhibits T-lymphocyte activation and proliferation that occurs secondary to antigenic and cytokine (IL-2, IL-4, and IL-15) stimulation. Specifically, sirolimus inhibits T-cell proliferation by binding a specific serine-threonine kinase (mTOR), which is necessary for cell cycle progression. Sirolimus also inhibits antibody production. It is important to note that sirolimus has an immunosuppressant action that is different from other immunosuppressant agents, including tacrolimus and cyclosporine. Remember that one of the primarily differences between sirolimus and both tacrolimus and cyclosporine is that this drug has minimal nephrotoxicity,
MOA Tolvaptan
Tolvaptan acts by selectively antagonizing vasopressin V2 receptors, increasing free water excretion.
Treat leishmaniasis with:
Sodium stibogluconate (antimony-containing compounds)
Maintenance dose equation
maintenance dose equation to answer this question: MD = CL x Cpss/F, where
MD = maintenance dose
CL = clearance
Cpss = plasma concentration at steady state
F = bioavailability
Mobitz type II
In Mobitz type II AV block, there are intermittent, non-conducted atrial beats not preceded by lengthening AV conduction. The PR interval remains unchanged in Mobitz type II AV block prior to a P wave that suddenly fails to conduct to the ventricles.
Drug efficacy
Efficacy is defined as the maximum effect that can be produced by a drug, regardless of dose.
Protamine
Reverses the effect of heparin
MOA: Sirolimus
Inhibits T-cell activation and proliferation by binding mTOR (a serine-threonine kinase that is instrumental in cell cycle progression)
Vincristine
Vincristine is a vinca alkaloid that inhibits mitosis in a cell cycle-dependent manner by blocking the formation of microtubules, thereby inhibiting neoplastic cell growth.
Vincristine is indicated for the treatment of Hodgkin and non-Hodgkin lymphoma, acute lymphoid leukemia, Ewing sarcoma, Wilms tumor, and several other types of malignancies.
Vincristine causes peripheral neuropathy.
Beta blockers and hypoglycemia
Symptoms of hypoglycemia include behavioral changes, confusion, fatigue, palpitations, tremor, anxiety, sweating, hunger, seizures, and even loss of consciousness.
Beta-adrenergic blockade may blunt or prevent some of the premonitory signs and symptoms of acute episodes of hypoglycemia mediated by the autonomic nervous system (e.g., sweats, tremor, nervousness, and tachycardia).
5-Fluorouracil
5-Fluorouracil (5-FU) is an antineoplastic agent and a fluorinated pyrimidine.
It is an analog of thymine in DNA (or uracil in RNA), and can impair DNA synthesis in actively proliferating cells.
Treatment for ventricular arrythmias
Lidocaine (choice C) is an antiarrhythmic agent indicated for the treatment of ventricular arrhythmias. Lidocaine has a variable effect on AV node conduction. For the most part, conduction through the AV node remains unchanged.
Procainamide (choice D) is a class IA antiarrhythmic agent indicated for the treatment of ventricular arrhythmias. It often causes AV node conduction to be slightly increased.
Cytarabine
cytarabine, a pyrimidine analogue, (choice A) plus daunorubicin OR idarubicin is used especially for induction treatment of acute myeloid leukemia (AML). Myelosuppression, anemia and thrombocytopenia are common adverse reactions.
Kernicterus
Kernicterus is the chronic and permanent neurologic sequelae of bilirubin-induced neurologic dysfunction (BIND). Brain regions most commonly affected include the basal ganglia and brainstem nuclei involved in oculomotor and auditory function.
Acute hyperbilirubinemia can lead to decreased alertness, hypotonia and poor feeding. Kernicterus is associated with opisthotonos, a high-pitched cry, an abnormal Moro reflex, and abnormal eye movements. Although kernicterus can occur pathologically, this condition may also occur if the mother takes sulfonamide antibiotics, such as trimethoprim-sulfamethoxazole or sulfisoxazole during the 2nd or 3rd trimester of pregnancy. Sulfonamides can displace bilirubin from its albumin-binding site, thereby increasing the serum concentration of free bilirubin available to cross the blood-brain barrier. Trimethoprim-sulfamethoxazole is not recommended for use in infants less than 2 months old. When hyperbilirubinemia occurs in an infant, the treatment of choice is to remove the bilirubin from the blood by phototherapy or exchange transfusion.
Amiodarone
Amiodarone is a class III antiarrhythmic with class IA antiarrhythmic properties.
It blocks potassium channels, prolongs repolarization, widens QRS, and prolongs the QT interval.
It is used to treat supraventricular and ventricular tachycardia, and is also used in the management of recurring ventricular tachycardia and fibrillation.
It causes torsades de pointes, hyper/hypothyroidism, pulmonary fibrosis, bradycardia, AV block as well as corneal deposits and blue/gray skin deposits resulting in photodermatitis.
Cyclobenzaprine
Cyclobenzaprine is a spasmolytic that is structurally related to the tricyclic antidepressants and has associated anticholinergic effects (dry mouth, impairment of urination and defecation, tachycardia) as well as sedation, confusion, and transient visual hallucinations.
Side effects: Atenolol
Atenolol is a selective beta-1-adrenergic receptor antagonist. In high doses, it can cause bradycardia and varying degrees of atrioventricular (AV) block. Additional side effects of atenolol include impotence, bradycardia, heart failure, and CNS adverse effects (sedation, seizures, sleep alterations).
Esters vs amides
An easy way to distinguish between the amides and esters are as follows: the amides have two “i’s” in their names and the esters have either one or no “i’s” in their name.
There are two classes of local anesthetics: esters and amides.
If you are allergic to one class, you will probably not be allergic to the other class.
Nephrotic syndrome
Nephrotic syndrome is a group of symptoms including proteinuria (exceeding 3.5 grams per day), hypoalbuminemia (normal 3.2 – 5 g/dL), and high cholesterol levels (total cholesterol > 200 mg/dL). Nephrotic syndrome is caused by a variety of disorders that lead to renal damage, particularly to the basement membrane of the glomerulus. This immediately causes abnormal excretion of protein in the urine.
What is epinephrine reversal?
Epi raises BP Phentolamine decreases BP Epi again this time decreases BP
PDE-5 inhibitors
Phosphodiesterase-5 (PDE5) inhibitors, such as sildenafil, tadalafil, and vardenafil, prevent the breakdown of cGMP.
The most common treatment for erectile dysfunction is with PDE5 inhibitors, such as sildenafil. During sexual stimulation, the release of nitric oxide (NO) is important for penile erection. NO activates guanylate cyclase, which converts GTP to cyclic guanosine monophosphate (cGMP). cGMP enhances smooth muscle relaxation in the corpus cavernosum and allows the inflow of blood and development of an erection. PDE5 inhibitors inhibit the phosphodiesterase that degrades cGMP, leading to increased levels of cGMP in the corpus cavernosum, increased smooth muscle relaxation, and increased inflow of blood. The PDE5 inhibitors cause flushing, nasal congestion, priapism and vision changes. These drugs are contraindicated for use with nitrates (nitroglycerine, isosorbide dinitrate, nitroprusside) since the combination may increase the risk of severe hypotension (synergistic effects).
Congenital syphilis
Congenital syphilis occurs in infants of untreated or inadequately treated mothers with syphilis, and is transmitted through the placenta to the fetus.
Cleft palate, rhinitis, and desquamating rash are classic signs of congenital syphilis.
Penicillin is the treatment of choice in nonpenicillin-allergic patients without neurosyphilis. In penicillin-allergic patients, oral doxycycline can be used.
Direct thrombin inhibitors include:
a direct thrombin inhibitor, such as bivalirudin, argatroban, danaparoid, or fondaparinux
Important digoxin drug interaction
Loop diuretics such as furosemide, torsemide, and ethacrynic acid cause hypokalemia and hypomagnesia, both of which contribute to digoxin toxicity.
Atropine
Atropine is a muscarinic receptor antagonist (choice A) used in the treatment of cholinesterase inhibitor poisoning.
Glucocorticoids and bone
Glucocorticoids also decrease intestinal calcium absorption, in part by opposing the effects of vitamin D as well as decreasing the expression of calcium channels in the duodenum. The glucocorticoids also increase renal calcium excretion by decreasing calcium reabsorption.
Use: Mupirocin
Mupirocin (choice E) is an antibacterial agent indicated for the topical treatment of impetigo primarily caused by Staphylococcus aureus or Streptococcus pyogenes.
MOA Methamphetamine
Methamphetamine acts by gaining entrance to dopamine, norepinephrine, and serotonin nerve terminals, causing therelease of these neurotransmitters via the uptake carriers. Dopamine is believed to play an important role in the reward system of the brain, and is thought to be a significant factor in the reinforcing effects of stimulants. One area of the brain that is thought to be involved in this reward system is the dopaminergic projection from the ventral tegmental area of the midbrain to the nucleus accumbens of the forebrain. By comparison, cocaine blocks the reuptake of dopamine and norepinephrine, and methylenedioxymethamphetamine (MDMA) causes the release of serotonin (5-HT).
Isotretinoin
Isotretinoin (choice C) is indicated for the treatment of severe recalcitrant acne. Its non-FDA approved uses include keratinization disorders, T-cell lymphoma, and various forms of skin cancers. It can be taken safely with antacids and milk products. This agent will decrease inflammation, sebum production and Propionibacterium acnes proliferation as well as follicular hyperproliferation and abnormal desquamation.
Esmolol
Esmolol and acebutolol are examples of a drugs that selectively antagonize beta-1-adrenergic receptors (choice C). They are used for supraventricular tachyarrhythmias, and would not cause PSVT or xanthopsia. Side effects include bradycardia, AV block, heart failure, and asthma exacerbation.
Phentolamine is an antagonist of what receptors?
alpha-1 alpha-2
Treat benzodiazepine overdose with:
Flumazenil
MOA Octreotide
Octreotide is a synthetic somatostatin analog that binds to receptors on carcinoid tumors and inhibits the synthesis and release of tumor hormones. Octreotide is very effective in reducing the flushing and diarrhea associated with carcinoid syndrome. It has been shown to reduce the excretion of 5-HIAA and to slow the growth of carcinoid tumors. It is generally well tolerated.
Sumatriptan
Sumatriptan (choice D) is a selective serotonin1D (5-HT1D) agonist. This agent is indicated for the treatment of acute migraine attacks with or without aura. Serious adverse effect of sumatriptan include coronary vasospasm, myocardial infarction, and severe hypertension.
Anticholinergic Toxidrome
“Red as a beet”: Cutaneous vasodilation (flushing) occurs to dissipate heat to compensate for lost of sweating.
“Dry as a bone”: Muscarinic receptors are on sweat glands, so blockade of these receptors stops sweating (anhidrosis), causing dry skin.
“Hot as a hare”: Interference with sweating can lead to hyperthermia.
“Blind as a bat”: Blocking muscarinic receptors on the ciliary muscle prevents accommodation (causing blurry vision). Muscarinic receptors on the pupillary sphincter muscle are also blocked, causing pupillary dilation (mydriasis).
“Mad as a hatter”: Blockade of central muscarinic receptors can cause anxiety, agitation, delirium, and hallucinations. (Hallucinations can actually make people seem larger or smaller, hence the Alice in Wonderland reference.)
Other side effects: Sinus tachycardia, decreased bowel sounds, and urinary retention.
MOA: Benzodiazepines
Benzodiazepines are used in the short-term management of alcohol withdrawal, panic disorder, and generalized anxiety disorder.
Benzodiazepines act by binding to the GABA-A receptor and increase the frequency of channel opening, which is a ligand-gated chloride channel.
In contrast to benzodiazepines, barbiturates increase the duration, rather than the frequency, of chloride ion channel opening. Benzodiazepine overdose can be treated with flumazenil. Note: flumazenil is ineffective for the treatment of barbiturate overdose.
Common beta-lactamase producing bacteria
Beta-lactamase producing bacteria include, Staphylococcus aureus, Haemophilus influenzae, Moraxella catarrhalis, Neisseria gonorrhoeae as well as Klebsiella and Enterobacter spp.
Bleomycin
Bleomycin (choice A) is an anticancer antibiotic and is one of the few chemotherapeutic agents that causes minimal bone marrow suppression. Its primary side effects include pulmonary fibrosis and pneumonitis. Bleomycin is used in Hodgkin lymphoma, testicular, head and neck, and skin cancers.
Tx of WPW
Regarding the treatment of WPW, antiarrhythmic agents, such as adenosine, amiodarone and verapamil, can alter the electrophysiologic mechanisms responsible for WPW, prolonging the refractory period of the conduction tissue and or the action potential.
Agents to treat bradycardia
atropine, isoproterenol, and dopamine
Treat acute angle glaucoma immediately with
Acetozolamide - will stop aqueous humor production by reducing bicarbonate
Complete heart block
In third-degree AV block there is no relationship between P waves and QRS complexes. Impulses are not transmitted through the AV node. A pacemaker develops in the ventricles, with both the atria and ventricles beating at their own rates because action potentials from the atria cannot reach the ventricles. Characteristics include a steady rhythm (usually) and very low ventricular heart rate (usually). There are no consistent PR intervals because impulses are not transmitted through the AV node. The rate for P waves (atrial depolarization) are different than the rate for R waves (first upward deflection after P wave; early ventricular depolarization).
Third-degree AV block is most commonly caused by coronary artery disease or degeneration of the cardiac conduction system with agents known to cause AV block.
Maraviroc
Maraviroc is a CCR5 receptor antagonist
Maraviroc acts by blocking HIV gp120 attachment and preventing viral cell entry.
Common adverse reactions include hepatotoxicity and orthostatic hypotension.
Bleomycin
Bleomycin (choice A) is an intercalating agent that complexes iron-forming reactive oxygen species and induces DNA strand breaks. It is used to treat squamous cell carcinoma, both Hodgkin and non-Hodgkin lymphoma as well as testicular carcinoma. This agent is commonly associated with the development of pulmonary fibrosis.
Prochlorperazine
Prochlorperazine (choice E) is a phenothiazine derivative used primarily to control severe nausea and vomiting by blocking central dopamine receptors.
Equation for anion gap
[Na+] − ([Cl−]+[HCO3−])
Buproprion
Bupropion is a norepinephrine and dopamine reuptake inhibitor antidepressant.
Patients with bulimia or anorexia nervosa should not be prescribed bupropion because of the increased risk of seizures.
Bupropion causes stimulant-like effects such as tachycardia, insomnia, and weight loss.
Does not cause sexual side effects.
Also used for smoking cessation.
Adverse effects of anticholinergic agents in the elderly
Drugs with anticholinergic properties:
Can precipitate angle-closure glaucoma
Can also cause cognitive impairment and delirium in the elderly, urinary retention, constipation, dry mouth, and tachycardia
Include diphenhydramine, amitriptyline, chlorpromazine, atropine, scopolamine, oxybutynin, tolterodine, benztropine, tropicamide, and meperidine
Benign Essential Tremor
Benign essential tremor is a progressive, bilateral, largely symmetric postural tremor of the upper extremities that is not associated with other neurologic symptoms.
Benign essential tremor can be successfully treated by propranolol, a nonselective beta-antagonist, and primidone, a barbiturate analog.
Use: Ribavarin
Ribavirin (choice E) is used in the treatment of respiratory syncytial virus infection in infants. This is the most common cause of hospitalization for respiratory disease in the very young, probably because aerosol administration of the antiviral compound is best accomplished in a hospital setting.
Penicillamine
Penicillamine is a chelating agent (choice B) used to chelate copper in Wilson disease and reduce excess cystine excretion in cystinuria. It is also used to treat cases of poisoning with copper, lead, arsenic, and gold, and is used in the treatment of severe rheumatoid arthritis.
Digoxin Toxicity
Characteristics of digoxin toxicity include nausea, vomiting, diarrhea, yellow-green (most commonly) distortion, and xanthopsia (yellow halos around lights). ECG changes include decreased QT interval, increased PR interval, T-wave inversion, almost any kind of arrhythmia (including PSVT), and AV block. Factors predisposing to digoxin toxicity include renal failure (decreased drug excretion), drug interactions (verapamil, quinidine, amiodarone) and hypokalemia (K+ competes with digoxin for binding sites on the Na+/K+-ATPase; hypokalemia results in increased digoxin binding).
Treat digoxin toxicity with digoxin immune Fab.
Fluphenazine
Typical high-potency antipsychotics, such as fluphenazine and haloperidol, are more likely to cause extrapyramidal side effects (EPS).
EPS include acute dystonia, drug-induced parkinsonism, akathisia, and tardive dyskinesia.
Note
The best way to distinguish stimulant overdose from anticholinergic overdose is the skin, which is sweaty with stimulants and dry with anticholinergics.
Methyldopa
Drugs used to treat chronic hypertension in pregnant women include methyldopa, labetalol, nifedipine, and hydralazine (for severe hypertension).
Methyldopa is converted to α-methylnorepinephrine, which is an alpha-2-adrenergic receptor agonist. Release of α-methylnorepinephrine in the medulla leads to a decrease in sympathetic outflow, which decreases blood pressure.
Acyclovir
Acyclovir is administered as a prodrug, which requires activation by the viral thymidine kinase and host cell kinases. Once activated, the drug inhibits the viral polymerase. It works to variable degrees with most of the Herpesviridae.
Red as a beet; Mad as a hatter; Hot as a hare; Blind as a bat; Dry as a bone.
Anticholinergic toxicity ie diphenhydramine antimuscarinic agent
Phenoxybenzamine
Phenoxybenzamine is the only non-competitive alpha-1 blocker used therapeutically in cases of malignant hypertension and pheochromocytomas. The excessive vasodilation produced by this agent is the result of irreversible binding to the receptor, thereby decreasing the efficacy (decreased curve height) of norepinephrine
MOA Heparin
Heparin acts at multiple sites in coagulation process. It binds to antithrombin III and catalyzes the inactivation of thrombin and other clotting factors.
Heparin-induced thrombocytopenia (HIT) is the most common type of drug-induced thrombocytopenia.
Milrinone
Milrinone is an inotrope are indicated for the short-term IV treatment of patients with acute decompensated heart failure. It inhibits phosphodiesterase (choice B), thus increasing cAMP levels and protein kinase A activation, which increases Ca2+ influx into the cardiac cell (see figure). Milrinone can cause a variety of arrhythmias, but is not associated with nausea or xanthopsia (yellow halos around lights).
MOA Ticlopidine
Similar to clopidogrel, ticlopidine irreversibly blocks ADP from binding platelets. Subsequently, ADP-induced expression of glycoprotein receptors is reduced, resulting in less fibrinogen binding.
Because aspirin and ticlopidine work through different mechanisms, they typically synergize. Ticlopidine may be used as a second-line agent to prevent thromboembolism or stroke. First-line therapy is typically clopidogrel in combination with aspirin because of the adverse side effects of ticlopidine. Roughly 2% of patients in clinical trials experienced neutropenia (Absolute Neutrophil Count (ANC) < 1500/mm3) or even agranulocytosis (ANC < 100/ mm3) with ticlopidine.
Give the equation for the anion gap:
[Na] - ([Cl]+[HCO3])
Cytarabine
Cytarabine (Ara-C) (choice C) is a pyrimidine analogue that inhibits DNA polymerase. It is used for leukemias and lymphomas and is associated with the development of leukopenia, thrombocytopenia, and megaloblastic anemia.
Note
Note: an easy way to remember beta-1 vs nonspecific beta antagonists is that antagonists that start with A through M (A-M-olol) are beta-1 specific and those that start with N through Z (N-Z-olol) are nonspecific.
Sodium thiosulfate
Sodium thiosulfate facilitates the rhodanese-catalyzed conversion of cyanide to less toxic thiocyanate (choice C). This agent is indicated for the treatment of cyanide overdose.
MOA Doxorubicin
Doxorubicin acts by hindering DNA replication and transcription by intercalating DNA. It also generates free radicals and inhibits topoisomerase II. Dexrazoxane can be used to decrease the incidence of doxorubicin cardiotoxicity.
A patient with cardiotoxicity secondary to doxorubicin may present with a persistently reduced voltage of the QRS complex, a prolonged systolic time interval, and a reduced ejection fraction.
Metronidazole and alcohol, why not?
Metronidazole should not be used in a patient with relapsing alcohol use disorder because the combination can cause a profound disulfiram reaction.
Nitrofurantoin
Nitrofurantoin (choice D) is most commonly used for the treatment and/or prophylaxis of urinary tract infections.
Triamterene
Triamterene (choice E) is a potassium-sparing diuretic. It inhibits sodium influx through channels in the luminal membrane of the late distal and cortical collecting tubules. Because potassium secretion is coupled with sodium entry in this area, potassium is spared.
Side Effects: Corticosteroids
Corticosteroids, such as methylprednisolone, are often associated with fluid and electrolyte imbalances such as water retention, hypernatremia, hypokalemia, and hypocalcemia, as well as hyperglycemia.
Treatment for tumor lysis syndrome
Patients who are about to receive chemotherapy for a cancer with high cell turnover rate, especially lymphomas and leukemias, should receive prophylactic oral or IV allopurinol for tumor lysis syndrome. Tumor lysis syndrome also includes hyperkalemia, hypocalcemia, and hyperphosphatemia. In addition to receiving prophylactic allopurinol, patients should receive adequate IV hydration, maintain high urine output, and alkalinize the urine with sodium bicarbonate. Febuxostat is an alternative xanthine oxidase inhibitor that can be used to treat tumor lysis syndrome.
Allopurinol is a prodrug (a suicide substrate) that is converted by the enzyme xanthine oxidase to alloxanthine (see figure). Alloxanthine inhibits xanthine oxidase, thus decreasing purine metabolism. This results in decreased uric acid formation and formation of uric acid stones.
MOA Cyclosporine and Tacrolimus
Cyclosporine (choice B) and tacrolimus (choice E) inhibit calcineurin-mediated transcription of the IL-2 gene and subsequently reduce T-cell activation. Cyclosporine and tacrolimus are limited by nephrotoxicity, whereas sirolimus has the advantage of minimal nephrotoxicity. However, sirolimus synergistically enhances cyclosporine-induced nephrotoxicity.
Mexiletine
Mexiletine and tocainide (both are available in PO formulations) have the same mechanism of action as lidocaine (IV only).
Class 1B antiarrhythmics block fast sodium channels, shortening the action potential duration (APD); this increases the threshold for excitation and decreases the excitability of hypoxic heart muscle.
Organophosphate Poisoning (AChEi)
DUMBELSis a common mnemonic used to remember effects of AChEI poisoning:
D: Diarrhea: stimulation of GI tract smooth muscle
U: Urination: stimulation of detrusor smooth muscle
M: Miosis: contraction of pupillary sphincter muscles
B: Bronchospasm/Bradycardia: increased stimulation of bronchial smooth muscle/decreased cardiac conduction
E: Emesis/Excitation of skeletal muscle: GI stimulation/stimulation of nicotinic receptors at neuromuscular junctions (NMJ)
L: Lacrimation: Increased glandular secretion (also other secretory glands)
S: Salivation/Sweating: Increased glandular secretion/increased stimulation of sympathetic cholinergic synapses at sweat glands
Treatment is with atropine and pralidoxime (2-PAM).
Macrolide antibiotics and CYP450
Clarithromycin is a macrolide antibiotic commonly used in the treatment of upper respiratory and skin/subcutaneous infections. It is a relatively potent hepatic microsomal enzyme inhibitor of the CYP3A4 system. Since clarithromycin is likely to potentiate the effects of theophylline, it could account for this patient’s symptoms.
Steady State
The half-life of a drug is clinically important because it determines the time required to reach steady-state and the dosage interval.
It takes four to five half-lives to reach steady-state.
The rule of thumb is that the plasma concentration will reach 50% in one half-life, 75% in two half-lives, 87.5% in three half-lives, etc.
How would you best treat RSV in babies?
Ribavirin - aerosol administration
Doxorubicin
Doxorubicin is an antineoplastic agent that can cause a congestive cardiomyopathy.
Cardiomyopathy/congestive heart failure is characterized by tachycardia, pulmonary rales, and a third heart sound (S3).
Doxorubicin is an antibiotic antineoplastic agent commonly used in the treatment of acute lymphocytic leukemia (ALL), acute myelogenous leukemia AML), Hodgkin lymphoma, and various solid tumors. It intercalates DNA, forms free radicals, and inhibits topoisomerase.
Hyperkalemia on EKG looks like
In hyperkalemia, the ECG usually first shows tall, peaked T waves, then prolongation of the PR interval, then absent P waves with widened QRS complexes, and finally ventricular tachycardia/ventricular fibrillation.
