Pharmacology in Pregnancy and Pediatrics

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Questions and Answers

What is a potential risk associated with using NSAIDs during the third trimester of pregnancy?

Increased risk of miscarriage

Decreased risk of delayed parturition

Reduced postpartum bleeding

Premature closure of the ductus arteriosus (correct)

A 7-month-old patient weighing 18 lbs requires ibuprofen at a dose of 5 mg/kg. Given that ibuprofen is available as a 100 mg/5 mL suspension, what is the appropriate single dose in mL?

4.0 mL

0.5 mL

2.0 mL (correct)

1.0 mL

An eight-year-old patient weighing 62 lbs with periorbital cellulitis is prescribed clindamycin at 20 mg/kg/day, divided into three doses. If the clindamycin solution is 75 mg/5 mL, how many mL are needed per daily dose?

24.8 mL

37.3 mL

12.4 mL

18.7 mL (correct)

Which of the following is generally considered an acceptable analgesic for a pregnant patient for headache relief?

Acetaminophen Signup and view all the answers

What is the most appropriate advice for a breastfeeding woman regarding analgesic usage for headaches?

Ibuprofen and acetaminophen are both generally acceptable Signup and view all the answers

What effect does valproic acid have on other drugs due to its interaction?

It displaces other drugs from protein-binding sites and can inhibit its own metabolism. Signup and view all the answers

Which of the following best describes the action of nonsteroidal anti-inflammatory drugs (NSAIDs) on COX enzymes?

They reversibly inhibit both COX-1 and COX-2. Signup and view all the answers

How do glucocorticoids affect the arachidonic acid pathway?

They inhibit PLA and downregulate the expression of COX-2. Signup and view all the answers

What is the primary role of the COX-1 enzyme according to the text?

To maintain cellular and vascular homeostasis. Signup and view all the answers

What is the effect of inhibiting COX enzymes on the metabolism of arachidonic acid (AA)?

It may shunt AA metabolism toward the production of leukotrienes. Signup and view all the answers

Which type of stimuli leads to the release of arachidonic acid from cell membranes by stimulating phospholipase A (PLA)?

Physical, chemical, inflammatory, and mitogenic stimuli. Signup and view all the answers

What is the effect of sulfonylureas when taken with drugs that interact with it?

Increased risk of hypoglycemia. Signup and view all the answers

What is the proposed mechanism of action of APAP as an analgesic?

Probably inhibits COX, although the pathway is not well understood. Signup and view all the answers

Which of the following best describes the mechanism of action of topical menthol?

Activation of TRP receptors causing a cooling sensation Signup and view all the answers

What is the primary function of the hypothalamus in relation to body temperature?

It monitors and regulates the core body temperature setpoint. Signup and view all the answers

A patient experiences a musculoskeletal injury resulting in localized pain. Which of the following mediators is NOT directly involved in the inflammatory response?

Erythromycin Signup and view all the answers

What is the mechanism of action of azole antifungals in treating vulvovaginal candidiasis?

They reduce ergosterol synthesis by inhibiting cytochrome P450 enzymes, which leads to a build-up of lanosterol-like sterols and structural membrane damage. Signup and view all the answers

A patient uses topical capsaicin for pain relief. The therapeutic action is primarily due to which mechanism?

Stimulation of the TRPV1 receptor and depletion of substance P. Signup and view all the answers

What is the role of pyrogens in the development of fever?

They activate the body's host defenses, leading to an increase in the hypothalamic set point. Signup and view all the answers

A topical medication is described as a 'rubefacient'. Which of the following best describes its action?

It increases the blood flow in the area of application. Signup and view all the answers

Which of these topical agents inhibits prostaglandin synthesis?

Trolamine salicylate Signup and view all the answers

Which of the following is a common symptom of atrophic vaginitis?

Vaginal dryness Signup and view all the answers

What is the primary mechanism of action of oxymetazoline as a decongestant?

Stimulates alpha-adrenergic receptors to constrict blood vessels Signup and view all the answers

Which type of cough is typically associated with acute bronchitis?

Clear cough Signup and view all the answers

What is a common side effect of first-generation antihistamines like diphenhydramine?

Sedation and dry mouth Signup and view all the answers

Why may patients taking intranasal corticosteroids need to avoid protease inhibitors?

To prevent Cushing's syndrome. Signup and view all the answers

Which of the following best describes the mechanism of action of cromolyn sodium?

It stabilizes mast cells by blocking calcium influx. Signup and view all the answers

Which medication used for cough has a potential for unpredictable clinical response due to CYP2D6 polymorphisms?

Codeine Signup and view all the answers

Which decongestant is known to cause rhinitis medicamentosa with overuse?

Oxymetazoline Signup and view all the answers

What is the primary role of histamine in the early phase of allergic rhinitis?

Causing rapid release of preformed mast cell mediators Signup and view all the answers

What is the action of adrenergic agonists as decongestants?

They stimulate alpha-adrenergic receptors Signup and view all the answers

What is considered a significant drug interaction associated with pseudoephedrine?

Increased risk of tachycardia with SNRIs Signup and view all the answers

Which of these first-generation antihistamines, also used as a sleep aid, is mentioned in the provided content?

Doxylamine Signup and view all the answers

What adverse effect is associated with long-term use of intranasal corticosteroids, specifically related to the eyes?

Glaucoma/Cataracts Signup and view all the answers

What is a common adverse effect of first generation antihistamines due to their anticholinergic effects?

Dryness of eyes and mucous membranes Signup and view all the answers

What is a distinguishing characteristic of diphenhydramine compared to second-generation antihistamines?

It has antitussive activity. Signup and view all the answers

What is the primary mechanism of action of pyrantel pamoate in treating pinworm infections?

Causing neuromuscular paralysis in adult worms. Signup and view all the answers

A patient needs a topical treatment for dry skin. Which of the following would be most appropriate in the context of dry skin?

Moisturizers such as creams or ointments Signup and view all the answers

Which of the following best describes the action of benzoyl peroxide in treating acne?

It possesses both keratolytic and antibacterial properties. Signup and view all the answers

What is the key difference between the mechanism of action of clotrimazole and tolnaftate when treating fungal infections?

Clotrimazole affects the biosynthesis of ergosterol, while tolnaftate inhibits squalene epoxidase. Signup and view all the answers

A patient with an erythematous, scaly, circular rash is suspected to have ringworm. Where is ringworm most likely located?

On smooth, bare skin, with the lesions beginning as small, circular, scaly areas. Signup and view all the answers

What is the primary reason why over-the-counter (OTC) options are typically ineffective for treating tinea unguium?

OTC products do no not penetrate the nail bed effectively. Signup and view all the answers

When using hydrocortisone 1% for atopic dermatitis, what is the recommendation regarding the duration of application?

Limit use to two weeks, followed by a week off. Signup and view all the answers

A patient comes to you seeking a treatment for photoaging; what would be the best recommendation from the selection below?

Glycolic acid because it is an alpha hydroxy acid that treats photoaging. Signup and view all the answers

What is the difference between using adapalene versus tretinoin for photoaging?

Tretinoin is the preferred medication because studies are based on it whereas adapalene is off-label. Signup and view all the answers

Which of the following best describes the mechanism of action for permethrin in treating pediculosis capitis?

Disruption of sodium channel currents in nerve cell membranes. Signup and view all the answers

What is the appropriate dose of pyrantel base?

11 mg per kg not to exceed 1 gram Signup and view all the answers

A patient is experiencing statin-associated adverse effects. Which supplement is most likely to be recommended to help with these effects?

Coenzyme Q10 Signup and view all the answers

Why might a physician recommend ergocalciferol (Vitamin D2) over cholecalciferol (Vitamin D3)?

Ergocalciferol is available by prescription only, allowing for more physician control. Signup and view all the answers

Which of the following is the most accurate description of how minoxidil functions to treat alopecia?

It acts as a vasodilator, increasing blood flow to hair follicles and stimulating hypertrophy. Signup and view all the answers

A patient with a known vitamin B12 deficiency asks about why they might have the deficiency. Which of the following is the MOST accurate response?

It may be due to decreased intrinsic factor, such as from age over 50, or taking metformin. Signup and view all the answers

A patient is seeking a natural alternative to statins for managing hypercholesterolemia. Which of the following would be most appropriate?

Red yeast rice Signup and view all the answers

Which of the following is NOT specifically mentioned as a condition for which Gingko biloba might be used?

Osteoporosis Signup and view all the answers

Which of the following best describes the primary use for topical vitamin E?

Minimization of scar formation Signup and view all the answers

Study Notes

Over-the-Counter (OTC) Drugs

Objectives for common OTC drugs: identify pathophysiology of diseases/disorders, mechanism of action (MOA) of drugs, adverse effects, and drug interactions.
Objectives for common vitamins, minerals, enzymes & herbs: identify diseases/disorders and acceptable products, and MOA (if noted).
Handbook of Nonprescription Drugs (20th edition) by Daniel L. Krinsky, Stefanie P. Ferreri, Brian A. Hemstreet, Anne L. Hume, Carol J. Rollins, Karen J. Tietze.

Headaches

Primary Headaches:
- Tension (episodic or chronic)
- Migraine (without or with aura)
- Cluster
Secondary Headaches:
- Stroke
- Substance abuse
- Infection
- Others...
Tension Headaches: Myofascial tissues & pericranial nociceptors, episodic peripheral nervous system, chronic central nervous system. 15+ days per month for three months.
Migraines (without aura): Pain pathways are stimulated; messenger molecules (nitric oxide, serotonin, calcitonin gene-related peptide.) Stimulation of trigeminal sensory fibers in large cerebral and dural vessels. Neuropeptide release occurs with consequent inflammatory and vasodilation, along with platelet/mast cell activation.
Migraines (with aura): Neuronal depolarization. Magnesium deficiency.
Sinus headaches & Estrogen withdrawal headaches.

Headaches - Characteristics

Tension-Type Headache:
- Bilateral location
- Diffuse ache, tightening, pressing, constricting nature
- Mild to moderate intensity
- Gradual onset
- 30 minutes to 7 days duration
- Aggravating factors: stress and anxiety.
- Non-headache symptoms: scalp tenderness, neck pain, and muscle tension.
Migraine Headache:
- Usually unilateral location
- Throbbing or pulsating nature
- Moderate to severe intensity
- Sudden onset
- 4-72 hours duration
- Aggravating factors: physical activity, light, sound, nausea, vomiting, aura
- Non-headache symptoms: None listed
Sinus Headache:
- Face, forehead, or periorbital area
- Pressure behind eyes or face, dull and bilateral pain.
- Mild to severe intensity
- Sudden onset
- Days – resolves with sinus symptoms
- Aggravating factors: Nasal congestion
- Non-headache symptoms: nasal congestion, nasal discharge

Acetaminophen (Tylenol / APAP)

Central inhibition of prostaglandin synthesis.
FDA warning about hepatotoxicity.
Metabolized in the liver by the cytochrome P450 enzyme system. Results in a hepatotoxic intermediate metabolite that is detoxified within Phase II conjugation with glutathione.
Treatment may include activated charcoal or acetylcysteine to supplement glutathione.

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)

Relieve pain through central and peripheral inhibition of cyclooxygenase (COX). With subsequent inhibition of prostaglandin synthesis.
Examples include Ibuprofen (Advil) and Naproxen (Aleve).
Adverse effects: GI ulceration, perforation, and bleeding, increased risk of myocardial infarction (MI), heart failure, hypertension and stroke, sodium/water retention causing edema, nephrotoxicity with chronic use.
Drug interactions: decreased clearance of methotrexate, increased risk of bleeding with P2Y12 inhibitors & SSRIs, increased risk of GI bleeding/ulceration with bisphosphonates, displacement from protein-binding sites with phenytoin.

Salicylates (aspirin)

Inhibits prostaglandin synthesis from arachidonic acid (by inhibiting both isoforms of the COX enzyme)
Uncommon intolerance: Cutaneous (urticaria, angioedema), respiratory (bronchospasm, laryngospasm, rhinorrhea)
Avoid in patients with gout, hyperuricemia, hypoprothrombinemia, vitamin K deficiency, hemophilia, or a history of bleeding disorders.
Contraindicated in children/teens with influenza or chicken pox (risk of Reye's syndrome)

Dosing (examples)

7-month-old, 18 lbs patient: Acceptable ibuprofen dose is based on weight (5 mg/kg). 100 mg/5 mL concentration of ibuprofen. The calculation determines the mL needed for the dose.
Eight-year-old patient with periorbital cellulitis: The provided ICD-10 code and patient weight are used to calculate the appropriate Clindamycin dosage.

Fever

Core body temperature regulated by hypothalamus and feedback system.
Pyrogens (exogenous or endogenous) activate body's host defenses, increasing set point.
Treat with APAP or ibuprofen (consider alternating).

Musculoskeletal Injuries and Disorders

Somatic pain transmission from peripheral nociceptors to the central nervous system.
Inflammatory response through multiple mediators, including histamine, bradykinin, serotonin, leukotrienes, and prostaglandin E.

Genitourinary System

Vulvovaginal Candidiasis (VVC):
- Thick, white ("cottage cheese") discharge without odor.
- Often associated with vaginal itching and irritation, and sometimes dysuria.
- The absence of a foul odor increases the likelyhood of VVC..
Bacterial Vaginosis (BV):
- Thin (watery), white, gray or sometimes foamy discharge.
- Characteristically has an unpleasant "fishy" odor, more pronounced after intercourse or menses.
- pH >4.5
Trichomoniasis:
- Frothy, malodorous, yellow-green or discolored discharge
- Symptoms may include vaginal irritation, pruritus, and dysuria. ~50% of infected women are initially asymptomatic.
Atrophic Vaginitis:
- Vaginal dryness, burning, itching, and dyspareunia (painful sexual intercourse).
Overactive Bladder:
- Oxybutynin patches (Oxytrol)
- Mechanism of action (MOA): antimuscarinic.

Respiratory System

Colds:
- Rhinoviruses, coronaviruses, parainfluenza, respiratory syncytial virus (RSV), adenoviruses, and human metapneumovirus.
- Viral infection that causes inflammation, congestion, sore throat, runny nose, cough, and possible fever.
Allergic rhinitis:
- Sensitization phase: allergen stimulates beta-lymphocyte-mediated IgE production.
- Early phase: rapid release of mast cell mediators (histamine, proteases, prostaglandins, kinins, leukotrienes). Cellular recruitment.
- Late phase: Leukocytes (eosinophils) attract to mucosa, release more inflammatory mediators, mucus hypersecretion.
Cough:
- Initiated by chemical and mechanical stimulation of sensory nerve terminals in the pharynx, larynx, esophagus, and tracheobronchial airway epithelium.
- "Clear" cough: usually associated with acute bronchitis (a bacterial infection.)
- "Purulent" cough: usually associated with a bacterial infection, could also be chronic bronchitis if persistent and associated with smoking.
Decongestants:
- Adrenergic agonists, stimulation of alpha-adrenergic receptors constrict blood vessels (reducing inflammation and swelling). Examples include phenylephrine and oxymetazoline.
- FDA warnings possible, limit use of certain sprays/medications.
Antihistamines:
- Compete with histamine at histamine type-1 (H₁) receptor sites.
- Second generations (ex. loratadine, cetirizine) are less sedating than first generations (ex. diphenhydramine).
Nasal Sprays: New to OTC market as of 2022. Azelastine 0.15%; indicated for the treatment of allergic and non-allergic rhinitis.
Intranasal Corticosteroids (INCS):
- Inhibit multiple mediators (e.g., histamine)
- Effective for allergic cascade
- Include: Budesonide, Fluticasone, Triamcinolone.
Cromolyn Sodium:
- Mast cell stabilizer, blocks calcium influx into mast cells (prevents degranulation, leukotriene release).
Antitussives (cough suppressants):
- Examples include Codeine; some have extensive metabolism and can be very dangerous in some patient populations.
- Some are opioids and should be avoided (excitement can lead to drug dependence.)
- Dextromethorphan (DM or DXM): noncompetitive antagonist for NMDA and glutamate (excitation.)
Expectorants:
- Guaifenesin (Mucinex): Loosens and thins respiratory tract secretions, making minimally-productive coughs more productive.

Gastrointestinal System

Heartburn: Acidic stomach content regurgitation via lower esophageal sphincter. Mucosal chemoreceptors trigger response.
Dyspepsia: discomfort/pain originates from stomach/duodenal area. May include symptoms such as persistent postprandial fullness (feeling full after eating) and early satiation (feeling full quickly). Could have epigastric pain (upper middle abdomen) and/or burning sensations.
Antacids:
- Onset: 5 minutes. Mechanism of action (MOA): buffering agents.
- Examples: Sodium bicarbonate, calcium carbonate, aluminum hydroxide, magnesium hydroxide, bismuth subsalicylate.
- Adverse effects: magnesium: diarrhea, avoid with CrCl <60 mL/min; aluminum: constipation; calcium: renal calculi (possible when already experiencing renal failure.); and, sodium bicarbonate: alkalosis (possible if preexisting impairment.)
- Drug interactions: chelation, doxycycline, ciprofloxacin, levofloxacin (amongst others).
H2 Receptor Antagonists (H2RAs):
- Onset: 30-45 minutes.
- MOA: inhibiting histamine (on H₂ receptors, which are on parietal cells, responsible for HCl production)
- Examples: cimetidine (Tagamet), famotidine (Pepcid) ranitidine (Zantac).
- Adverse effects: cimetidine: antiandrogenic effect (decreased libido, impotence, gynecomastia.)
Proton Pump Inhibitors (PPIs):
- Onset: 60 minutes (can take several days to reach full efficacy),
- MOA: inhibit hydrogen-potassium ATPase (the proton pump), which blocks the final step in gastric acid secretion.
- Examples: omeprazole (Prilosec), esomeprazole (Nexium), lansoprazole (Prevacid), pantoprazole (Protonix).
- Adverse effects: C. difficile infection, increased risk for spontaneous bacterial peritonitis in those with cirrhosis, and osteoporosis-related fractures.
Constipation:
- Polyethylene glycol 3350 (Miralax): hyperosmotic, increases osmolality in the GI canal, water/solutes move into canal and thus, relief of constipation.
- Wheat dextrin (Benefiber): Fiber supplement
- Docusate (Colace): stool softener.
- Magnesium citrate: saline laxative.
- Bisacodyl (Dulcolax): stimulant laxative.

Ophthalmic and Otic Products

Dry eye and allergic conjunctivitis:
- Includes: phenylephrine, naphazoline, oxymetazoline, tetrahydrozoline, brimonidine, olopatadine, Ketotifen.
Excess cerumen:
- Carbamide peroxide (6.5% in anhydrous glycerin) – Debrox (ear drops)

Dermatologic Disorders

Atopic Dermatitis:
- Characterized as dry, chronically inflamed, scaly skin in plaques, papules, and/or vesicles.
- May be affected areas by red, raised, plaques with exudate (fluid leaks from blisters and/or pustules).
- Inflammation due to increased cytokines (IL-4 and IL-13)
- Treatment includes topical hydrocortisone. Treatment includes topical corticosteroids.
Xerosis:
- Dry skin; treatments include moisturizers: creams, ointments, lotions.
Acne:
- Multifactorial disorder of the pilosebaceous glands.
- Adapalene (Differin), retinoid, benzoyl peroxide (2.5% - 10%); keratolytic and antibacterial properties, bleach fabrics.
- Salicylic acid (0.5 - 2%) – comedolytic.
- Sulfur (3% - 10%) – keratolytic and antibacterial.
- Photoaging - Glycolic Acid (derivative of Vitamin A-Alpha hydroxy acid), Tretinoin 0.5%, Retinol)
Minimizing scarring (skin):
- Silicon sheeting or gels, Vitamin E liquid.
Warts:
- HPV infection of basal keratinocytes.
- Treatments include: salicylic acid, cryotherapy.
Alopecia (hair loss):
- Minoxidil 2 - 5% (Rogaine), vasodilator, increases cutaneous blood flow around follicles, increase in follicle hypertrophy.
Pediculosis capitis (lice):
- Pediculus humanus capitis
- Treatments: Permethrin 1% (Nix) (Acts on sodium channels in nerve cells), Ivermectin 0.5% (Sklice) (acts on glutamate-sensitive chloride channel currents in helminths).

Vitamins, Minerals, Enzymes & Herbs

Vitamin B12 (cyanocobalamin):
- Macrocytic anemia, decreased intrinsic factor (particularly in older adults and patients with metformin).
Vitamin B9 (folic acid):
- Neural tube defects.
Calcium and vitamin D:
- Osteoporosis, Vitamin D dosing in IU's (international units) is still common practice, but conversion to mcg is encouraged to avoid errors/confusion in dosing.
Iron:
- Microcytic anemia.
Vitamin E:
- Topically for minimizing scars.
Coenzyme Q10:
- Rate-limiting cofactor in mitochondrial ATP formation.
- Reduces statin-associated adverse effects.
Fish oil:
- Omega-3 fatty acids: DHA/EPA.
Red Yeast Rice:
- Molecular structure similar to statins, useful for hypercholesterolemia.
Niacin (Vitamin B3):
- NAD & NADP for mitochondrial redox (reductive-oxidative reactions)
- Useful for hypercholesterolemia.
Ginkgo biloba:
- Neuroprotective properties.
- For treatment of Alzheimer's, dementia, ADHD, tardive dyskinesia, intermittent claudication, tinnitus, acute mountain sickness, age-related macular degradation.
Melatonin:
- Hormone and potent antioxidant (pineal gland).
- Useful for insomnia and jet lag.
St. John's wort:
- Hypericum perforatum flower, useful for depression, anxiety, and OCD.
Valerian root:
- Valeriana officinalis, useful for insomnia and anxiety.
Kava:
- Piper methysticum, ceremonial tranquilizers for Pacific Islanders.
- May cause severe liver damage.
Kratom:
- Mitragyna speciosa, psychoactive effects (both stimulant and opioid-like).
CBD:
- Cannabis sativa.
Probiotics:
- GI flora restorations; Florajen, VSL
Glucosamine and Chondroitin:
- Stimulates chondrocytes (cartilage production), synoviocytes (synovial fluid production), and inhibits matrix metalloproteinase and inflammatory cytokines.
Saw palmetto:
- Inhibits 5-alpha-reductase and cytosolic androgen receptor. Treatment for BPH (benign prostatic hyperplasia)
Black cohosh:
- Cimicifuga racemose, useful for premenstrual syndrome, dysmenorrhea, and menopause.
Evening primrose oil:
- Oenothera biennis, useful for PMS and menopause.

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Description

This quiz focuses on the pharmacological considerations when prescribing medications to pregnant women and pediatric patients. It covers the use of NSAIDs, dosage calculations, and the interactions of specific drugs, providing a holistic view of safe practices in medicine. Test your knowledge on proper analgesic options and important drug interactions.