Drugs for Fertility/ Drugs for Pregnancy Flashcards
Which medication is most appropriate for treating erectile dysfunction in patients who also have antidepressant-induced erectile dysfunction?
A. Alprostadil
B. Sildenafil
C. Clomipramine
D. Flibanserin
B. Sildenafil: Correct. PDE5 inhibitors like sildenafil are the drugs of choice for erectile dysfunction, including cases induced by antidepressants.
A. Alprostadil: Incorrect. Alprostadil is typically used when PDE5 inhibitors are ineffective or contraindicated, not as the first-line treatment for erectile dysfunction.
C. Clomipramine: Incorrect. Clomipramine is used for premature ejaculation, not erectile dysfunction.
D. Flibanserin: Incorrect. Flibanserin is approved for female sexual interest/arousal disorder, not male erectile dysfunction.
Which of the following is a common adverse effect of PDE5 inhibitors?
A. Priapism
B. Nasal congestion
C. Permanent vision loss
D. Chest pain
B. Nasal congestion: Correct. Nasal congestion is a common adverse effect of PDE5 inhibitors, along with headache flushing, and dyspepsia. These occur because PDE5 inhibitors enhance blood flow, which can also lead to increased vascular congestion in mucosal tissues.
A. Priapism: Incorrect. Priapism is a rare but serious adverse effect, not a common one.
C. Permanent vision loss: Incorrect. While rare, permanent vision loss is a potential adverse effect, but it is not common.
D. Chest pain: Incorrect. Chest pain may occur but is a rare and serious adverse effect requiring emergency care.
In female sexual interest/arousal disorder (FSIAD), which therapy is approved for low sexual desire in premenopausal patients?
A. Testosterone supplementation
B. Flibanserin
C. Sildenafil
D. Vaginal DHEA
**B. Flibanserin: Correct. Flibanserin is a serotonin agonist/antagonist approved for low sexual desire in premenopausal women. Its action on serotonin and dopamine pathways is thought to balance neurotransmitters associated with sexual desire. However, its use is limited due to modest efficacy, a daily dosing requirement, and risks of adverse effects like syncope when combined with alcohol.
**
A. Testosterone supplementation: Incorrect. Testosterone is not approved for women and lacks robust safety data for use in FSIAD.
C. Sildenafil: Incorrect. Sildenafil has not been found useful for female sexual dysfunction.
D. Vaginal DHEA: Incorrect. Vaginal DHEA is used to improve genital sensitivity and dyspareunia but is not specifically approved for FSIAD.
What is the most appropriate pharmacologic intervention for genitourinary syndrome of menopause (GSM)?
A. Systemic testosterone
B. Intravaginal estrogen
C. Sodium cromoglycate
D. PDE5 inhibitors
B. Intravaginal estrogen: Correct. Intravaginal estrogen is effective in restoring vaginal health, increasing blood flow, and managing symptoms of GSM.
A. Systemic testosterone: Incorrect. Testosterone supplementation is not approved for GSM.
C. Sodium cromoglycate: Incorrect. Sodium cromoglycate is used for provoked vestibulodynia, not GSM.
Vestibulodynia - is chronic or recurrent pain localized at the area surrounding the vaginal opening.
D. PDE5 inhibitors: Incorrect. PDE5 inhibitors are not indicated for GSM.
Which antidepressant is considered “sexually neutral” and less likely to cause sexual dysfunction?
A. Citalopram
B. Venlafaxine
C. Mirtazapine
D. Paroxetine
C. Mirtazapine: Correct. Mirtazapine is considered “sexually neutral” and less likely to cause sexual dysfunction.
Mirtazapine is classified as a tetracyclic antidepressant (TeCA) and is primarily used to treat major depressive disorder (MDD)
A. Citalopram: Incorrect. Citalopram, like most SSRIs, is associated with sexual dysfunction.
B. Venlafaxine: Incorrect. Venlafaxine, an SNRI, also has a higher risk of causing sexual dysfunction.
D. Paroxetine: Incorrect. Paroxetine is associated with a high risk of sexual dysfunction.
Mechanism of action of Mirtazapine:
Mechanism of Action
Antagonist at α2-adrenergic receptors: Inhibits the α2-autoreceptors and heteroreceptors, enhancing the release of norepinephrine and serotonin. This disinhibition increases neurotransmitter availability, improving mood.
Serotonin receptor modulation:
Blocks 5-HT2A, 5-HT2C, and 5-HT3 receptors, promoting the activity of the 5-HT1A receptor, which has mood-enhancing effects.
The blockade of 5-HT3 reduces nausea and gastrointestinal side effects often seen with selective serotonin reuptake inhibitors (SSRIs).
Histamine H1 receptor antagonist: Causes sedative effects, making it useful for individuals with insomnia associated with depression.
Minimal activity on serotonin or norepinephrine reuptake: Unlike SSRIs or SNRIs, mirtazapine does not inhibit reuptake but enhances neurotransmitter levels through receptor modulation.
Indications
Major depressive disorder (MDD): Particularly in patients with insomnia or poor appetite due to its sedative and appetite-stimulating effects.
Off-label uses: Anxiety disorders, post-traumatic stress disorder (PTSD), and as an adjunct in other psychiatric conditions.
Adverse Effects
Sedation: Due to strong H1 receptor antagonism.
Weight gain: Caused by increased appetite through histamine and serotonin receptor modulation.
Dry mouth, dizziness, and constipation: Common side effects.
Unique Features
Unlike SSRIs and SNRIs, mirtazapine is less likely to cause sexual dysfunction and gastrointestinal issues.
Its sedative properties make it a dual-purpose medication for depression with insomnia.
In summary, mirtazapine is a tetracyclic antidepressant with a unique receptor-targeting profile, offering therapeutic benefits for depression with a side effect profile that may suit certain patient populations better than other antidepressants.
Which of the following is true regarding the use of PDE5 inhibitors in erectile dysfunction?
A. Absorption of sildenafil is delayed by high-fat meals.
B. Tadalafil has the shortest duration of action.
C. PDE5 inhibitors are safe to combine with nitrates.
D. Sildenafil is ineffective for premature ejaculation.
A. Absorption of sildenafil is delayed by high-fat meals: Correct. High-fat meals can delay sildenafil absorption.
B. Tadalafil has the shortest duration of action: Incorrect. Tadalafil has the longest duration of action, lasting up to 36 hours.
C. PDE5 inhibitors are safe to combine with nitrates: Incorrect. PDE5 inhibitors are contraindicated with nitrates due to the risk of severe hypotension.
D. Sildenafil is ineffective for premature ejaculation: Incorrect. Sildenafil may be beneficial for premature ejaculation, sometimes exceeding the benefits of antidepressants.
What drugs/substances effects the fetus
ACE Inhibitors: These are contraindicated in pregnancy, particularly after the first trimester, due to risks of fetal renal dysgenesis and oligohydramnios, which can lead to growth restriction and neonatal complications. Alternate medications, like labetalol or nifedipine, are preferred for managing hypertension in pregnancy.
Ondansetron (Zofran): While not a first-line option, Zofran is commonly prescribed for hyperemesis gravidarum (severe nausea/vomiting) when other options, like vitamin B6 and doxylamine, fail. There’s slight evidence of association with oral clefts, but overall, it is considered safe when necessary.
Aspirin: Safe in low doses (<150 mg/day) in the first and second trimesters to prevent complications like preeclampsia. Discontinue in the third trimester due to risks like ductus arteriosus closure and increased bleeding.
Acetaminophen (Tylenol): Preferred analgesic throughout pregnancy when used at the lowest effective dose for the shortest duration. Long-term or high-dose use has been linked (weakly) to potential neurodevelopmental concerns, but these risks are minimal compared to alternatives.
Why are statins discouraged during pregnancy?
Statins work by inhibiting HMG-CoA reductase, an enzyme essential for cholesterol synthesis in the liver. While this is beneficial for reducing high cholesterol levels in non-pregnant individuals, it can interfere with the natural increase in cholesterol during pregnancy, which is critical for:
Hormone Production:
Cholesterol, primarily from LDL, is a precursor for steroid hormones like estrogen, progesterone, and cortisol.
These hormones are essential for maintaining pregnancy, supporting placental function, and preparing the body for labor.
Fetal Development:
Cholesterol is vital for cell membrane formation, brain and nervous system development, and overall fetal growth.
Interfering with cholesterol synthesis during critical developmental periods could lead to adverse outcomes.
Placental Function:
The placenta uses maternal cholesterol to produce hormones needed to sustain the pregnancy.
Why Statins Are Contraindicated:
Potential Teratogenicity: By disrupting cholesterol synthesis, statins may impair fetal development, particularly in the first trimester when organogenesis (organ formation) occurs.
Lipid Elevation Is Physiological: Pregnancy-associated hyperlipidemia is normal and supports both maternal and fetal needs. Lowering lipid levels with statins could negatively affect these processes.
Clinical Implications:
Pregnant women with hyperlipidemia are typically managed with dietary modifications and lifestyle changes rather than medications like statins.
For women with severe hyperlipidemia or familial hypercholesterolemia, close monitoring and alternative strategies may be considered, but statins remain avoided due to their risks.
Why do statins cause myopathy and what does HMg-coA stand for?
Inhibition of HMG-CoA Reductase:
Statins inhibit the enzyme HMG-CoA reductase, which plays a key role in the mevalonate pathway for cholesterol synthesis.
This pathway also produces important molecules like coenzyme Q10 (ubiquinone), essential for energy production in muscle mitochondria. Reduced coenzyme Q10 levels may impair energy production and increase muscle cell susceptibility to damage.
Disruption of Muscle Cell Membranes:
Cholesterol is a structural component of cell membranes. Lowered cholesterol levels can compromise the integrity of muscle cell membranes, making them more prone to injury.
Increased Muscle Breakdown:
Statins may increase muscle protein degradation and alter muscle repair mechanisms, leading to symptoms like pain, weakness, and, in severe cases, rhabdomyolysis (massive muscle breakdown).
Genetic Susceptibility:
Variants in the SLCO1B1 gene affect the uptake of statins into the liver, leading to higher blood levels of the drug and increased risk of myopathy.
HMG-CoA stands for 3-Hydroxy-3-Methylglutaryl-Coenzyme A.
Role in Metabolism:
HMG-CoA is an intermediate in two important metabolic pathways:
Cholesterol Synthesis (Mevalonate Pathway):
HMG-CoA is converted into mevalonate by the enzyme HMG-CoA reductase. This step is the rate-limiting step in cholesterol production.
Ketogenesis:
In the liver, HMG-CoA can also be converted into acetoacetate, a type of ketone body, during periods of low glucose availability (e.g., fasting or ketogenic diet).
Summary
Statins cause myopathy due to disruptions in cholesterol and coenzyme Q10 synthesis, structural integrity of muscle cells, and genetic factors.
HMG-CoA is a critical molecule in cholesterol and ketone body synthesis, with its full name reflecting its chemical structure and role as a coenzyme derivative.
Which pharmacologic option is considered the first-line treatment for venous thromboembolism (VTE) during pregnancy?
A) Warfarin
B) Low-Molecular-Weight Heparin (LMWH)
C) Unfractionated Heparin (UFH)
D) Aspirin
Correct Answer: B) Low-Molecular-Weight Heparin (LMWH)
Why it’s correct: LMWH is the preferred treatment in pregnancy due to its safety profile (does not cross the placenta) and efficacy. Lowers risks of bone loss and
thrombocytopenia.
* Weight-adjusted dosing: 1 mg/kg twice daily.
Why others are incorrect:
A: Warfarin is contraindicated during pregnancy due to teratogenic risks (e.g., embryopathy, fetal CNS defects). It is safe postpartum and compatible with breastfeeding.
C: UFH is a second-line option with higher risks of osteoporosis and heparin-induced thrombocytopenia.
D: Aspirin is not the standard treatment for VTE.
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is unfractionated heparin smaller than LMWH and what does that stand for?
No, Unfractionated Heparin (UFH) is actually larger than Low-Molecular-Weight Heparin (LMWH) in terms of molecular size.
UFH consists of a mixture of long polysaccharide chains of varying molecular weights (typically 5,000–30,000 Daltons).
LMWH is derived from UFH but is enzymatically or chemically cleaved to have shorter chains (usually 1,000–10,000 Daltons), making it more predictable in action.
Abbreviations Explained:
UFH = Unfractionated Heparin
LMWH = Low-Molecular-Weight Heparin
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Why Is UFH Used Closer to the Due Date?
UFH is preferred near delivery for a few key reasons:
Shorter Half-Life
UFH has a short half-life (~1–2 hours), meaning its effects wear off quickly after stopping the infusion.
This is important because if a patient goes into labor or needs an emergency C-section, stopping UFH reduces the risk of excessive bleeding during delivery.
Reversible with Protamine Sulfate
UFH can be fully reversed using protamine sulfate, a medication that neutralizes its anticoagulant effects.
This is crucial if an urgent C-section or epidural anesthesia is needed.
Safer for Epidural or Spinal Anesthesia
LMWH stays active longer and carries a higher risk of spinal hematoma if used too close to epidural placement.
UFH is preferred because its effect wears off faster, making it safer for epidurals or spinal anesthesia during labor.
How is the Transition from LMWH to UFH Managed?
Around 36 weeks, many pregnant patients on LMWH are switched to UFH.
UFH is then stopped ~4–6 hours before labor induction or a planned C-section to minimize bleeding risks.
After delivery, anticoagulation is restarted based on the patient’s risk factors for clotting.
Would you like a clinical scenario or case example to illustrate this transition? 😊
You said:
why does UFH have a shorter half life if it is larger than LMWH
ChatGPT said:
ChatGPT
Great question! Even though Unfractionated Heparin (UFH) is larger than Low-Molecular-Weight Heparin (LMWH), it has a shorter half-life due to differences in how it is metabolized and cleared from the body. Here’s why:
- Metabolism & Clearance
UFH is rapidly cleared by the reticuloendothelial system (RES)
UFH binds to macrophages and endothelial cells, which quickly remove it from circulation.
This results in a short, dose-dependent half-life (~1–2 hours).
LMWH is cleared mainly by the kidneys
LMWH has a more predictable and slower clearance because it is eliminated renally (by the kidneys).
This gives LMWH a longer half-life (~4–6 hours or more, depending on the dose and patient factors). - Binding to Plasma Proteins
UFH binds to many plasma proteins, making its effect variable and short-lived.
LMWH binds less to plasma proteins, so it stays in circulation longer and has a more predictable anticoagulant effect. - Mechanism of Action & Molecular Size
UFH (~15,000 Da):
Because UFH is large, it can bind both antithrombin (AT) and thrombin (Factor IIa), allowing for strong anticoagulation but also making it susceptible to faster clearance by endothelial cells.
LMWH (~4,500 Da):
Since LMWH is smaller, it mainly inhibits Factor Xa more than thrombin, making its effect more stable and prolonged.
Summary of Why UFH Has a Shorter Half-Life Despite Being Larger
Rapid clearance by endothelial cells/macrophages → Short half-life
More plasma protein binding → Less predictable effect
Dual action on Factor Xa and thrombin → Faster removal from circulation
This is why UFH is used closer to delivery, as it allows for quick reversal and minimizes bleeding risks in case of labor or C-section.
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but why is UFW cleared by macrophages and LMWH cleared by the renal system is it because it is smaller
ChatGPT said:
ChatGPT
Yes, molecular size plays a major role, but there are also structural and biochemical differences that determine how Unfractionated Heparin (UFH) and Low-Molecular-Weight Heparin (LMWH) are cleared from the body. Here’s why:
- Why UFH Is Cleared by Macrophages & Endothelial Cells
UFH is much larger (~15,000 Da) and highly negatively charged, which makes it more likely to bind to cells in the reticuloendothelial system (RES) (including macrophages and endothelial cells).
The RES (mainly in the liver and spleen) recognizes UFH as a foreign substance and rapidly removes it from circulation.
This non-renal clearance means UFH is safer in patients with kidney disease because it doesn’t depend on the kidneys for elimination. - Why LMWH Is Cleared by the Kidneys
LMWH is smaller (~4,500 Da) and has fewer binding sites for macrophages and endothelial cells.
Since LMWH does not bind to these cells as much, it remains in circulation longer and is eventually filtered by the kidneys.
Because LMWH is renally excreted, it accumulates in patients with kidney disease, which is why dose adjustments are needed in renal impairment. - Does Molecular Size Explain the Clearance Difference?
Yes, size is a major factor, but it’s also about how heparin molecules interact with proteins and cells in the body.
UFH’s large, irregular structure means it binds non-specifically to various proteins and cells, making it susceptible to rapid clearance by macrophages.
LMWH, being smaller and more uniform, does not bind as much and is instead filtered by the kidneys.
Key Takeaways
Feature UFH (Unfractionated Heparin) LMWH (Low-Molecular-Weight Heparin)
Size ~15,000 Da ~4,500 Da
Clearance Mechanism Reticuloendothelial System (macrophages, endothelial cells) Renal clearance (kidneys)
Half-life Short (~1–2 hours) Longer (~4–6 hours)
Dosing Consideration Safer in kidney disease Dose adjustment needed in kidney disease
Why Does This Matter Clinically?
UFH is used near delivery because it clears quickly, reducing the risk of excessive bleeding during labor or C-section.
LMWH is preferred for long-term anticoagulation but must be adjusted in renal impairment.
Which of the following medications is contraindicated during pregnancy for insomnia?
A) Zolpidem
B) Benzodiazepines
C) Doxylamine
D) Hydroxyzine
Correct Answer: B) Benzodiazepines
Why it’s correct: Benzodiazepines are contraindicated in pregnancy due to risks of spontaneous abortion, preterm birth, and floppy infant syndrome.
Why others are incorrect:
A: Zolpidem is generally considered safe but can cause low birth weight and neonatal withdrawal.
C: Doxylamine is safe for short-term use.
D: Hydroxyzine is commonly used but should be prescribed with caution due to its ability to cross the placenta.
Which of the following pharmacologic treatments is preferred for insomnia during pregnancy?
A) Benzodiazepines
B) Diphenhydramine
C) Hydroxyzine
D) Doxylamine
Correct Answer: D) Doxylamine
Explanation:
D) Doxylamine: Safe and effective for short-term use in pregnancy, it is an antihistamine.
A) Benzodiazepines: Associated with significant fetal risks like floppy infant syndrome and preterm birth.
B) Diphenhydramine: Limited benefit and risk of neonatal withdrawal with chronic use.
C) Hydroxyzine: Crosses the placenta and may cause neonatal withdrawal symptoms with chronic use.
Which antacid is preferred for heartburn in pregnancy?
A. Aluminum hydroxide
B. Calcium carbonate
C. Sodium bicarbonate
D. Magnesium trisilicate
B. Calcium carbonate
Correct. Calcium carbonate is preferred in pregnancy because:
It effectively neutralizes stomach acid.
It provides an additional source of calcium, which is beneficial during pregnancy.
Side effects are mild (e.g., constipation in some cases).
A. Aluminum hydroxide
Incorrect. While aluminum-containing antacids can neutralize stomach acid, they are not preferred in pregnancy due to the risk of maternal constipation and potential harm to the fetus if used in high doses.
C. Sodium bicarbonate
Incorrect. Sodium bicarbonate is not recommended in pregnancy because it can cause fluid retention and systemic alkalosis, which can be harmful to both the mother and fetus.
D. Magnesium trisilicate
Incorrect. Magnesium trisilicate is generally avoided in pregnancy because of concerns about its safety for the fetus and the potential for adverse gastrointestinal effects in the mother.
Why are statins contraindicated during pregnancy?
A) They cause hyperlipidemia, leading to maternal complications.
B) They inhibit LDL, which is a precursor for sex hormone production.
C) They increase the risk of gestational diabetes.
D) They elevate triglyceride levels, leading to pancreatitis.
B) They inhibit LDL, which is a precursor for sex hormone production.
Correct: LDL is required for synthesizing hormones like estrogen and progesterone, which are critical during pregnancy.
A) They cause hyperlipidemia, leading to maternal complications.
Wrong: Pregnancy-related hyperlipidemia is normal and not caused by statins
C) They increase the risk of gestational diabetes.
Wrong: Statins are not directly linked to GDM risk.
D) They elevate triglyceride levels, leading to pancreatitis.
Wrong: Statins typically lower triglyceride levels, not elevate them.
More information
2. What is the Precursor for Hormones: VLDL, LDL, or HDL?
Correct Answer:
During pregnancy, elevated lipid levels (including VLDL, LDL, and HDL) are normal physiological adaptations that serve important roles:
LDL (Low-Density Lipoprotein): The primary precursor for steroid hormone synthesis, such as estrogen, progesterone, and cortisol, which are critical for maintaining pregnancy, preparing the body for labor, and supporting fetal development. The placenta uses cholesterol from LDL for hormone production.
VLDL (Very Low-Density Lipoprotein): Provides energy storage and transports triglycerides, but it is not the primary precursor for hormone synthesis.
HDL (High-Density Lipoprotein): While HDL helps in cholesterol transport and balance, it is not the major source of cholesterol for hormone synthesis.
This is why statins are normally discouraged during pregnancy
What is the primary goal of stepwise asthma treatment during pregnancy?
a) Minimizing medication use
b) Maximizing fetal exposure to oxygen
c) Reducing maternal weight gain
d) Avoiding all inhaled corticosteroids
Correct Answer: b) Maximizing fetal exposure to oxygen
Explanation: Asthma management during pregnancy prioritizes optimal oxygenation for both the mother and fetus. Inhaled corticosteroids are commonly used when needed to achieve this.
