Contraindications - Pharmacy Technician Certification Exam Ptce
- Which medication is contraindicated in patients with narrow-angle glaucoma due to anticholinergic effects?
- Anticholinergics (for example, oxybutynin). Anticholinergic effects can increase intraocular pressure, potentially precipitating acute angle-closure glaucoma.
- Which opioid is contraindicated in patients taking MAO inhibitors due to serotonin syndrome risk?
- Meperidine. Meperidine's serotonergic properties combined with MAO inhibition cause serotonin accumulation and syndrome.
- Which medication is contraindicated with any nitrate therapy (for example, nitroglycerin)?
- PDE-5 inhibitors (for example, sildenafil). Concurrent use potentiates vasodilation, leading to severe hypotension and increased risk of cardiovascular events.
- Which drug is contraindicated in patients with severe renal impairment because of lactic acidosis risk?
- Metformin. Renal impairment reduces metformin clearance, leading to accumulation and increased risk of life-threatening lactic acidosis.
- Which analgesic class is contraindicated in patients with a history of aspirin-exacerbated respiratory disease?
- Nonselective NSAIDs (including aspirin). These agents can trigger severe bronchospasm and exacerbations in patients with aspirin sensitivity via leukotriene pathway.
- Which condition is an absolute contraindication to isotretinoin therapy?
- Pregnancy. Isotretinoin is highly teratogenic, causing severe fetal abnormalities and thus absolutely contraindicated in pregnant patients.
- Which antibiotic is contraindicated in children due to tooth discoloration and inhibited bone growth?
- Tetracyclines (for example, doxycycline). Tetracyclines bind to developing teeth and bones, causing permanent enamel hypoplasia and skeletal growth inhibition.
- Which diabetes medication class is contraindicated in type 1 diabetes due to ketoacidosis risk?
- SGLT2 inhibitors (for example, empagliflozin). These inhibitors promote euglycemic ketoacidosis in type 1 diabetes by increasing ketone production without hyperglycemia.
- Which drug is contraindicated in patients with severe hepatic disease due to risk of hepatotoxicity?
- Disulfiram. Disulfiram's metabolism can further impair liver function, increasing the risk of acute hepatic failure in compromised patients.
- Which anticoagulant is contraindicated in patients with active major bleeding?
- Any anticoagulant (for example, warfarin, apixaban, heparin). Anticoagulants increase bleeding risk in patients with active hemorrhage by inhibiting clotting mechanisms.
- Which drug class is contraindicated in pregnancy due to fetal renal toxicity and malformations?
- ACE inhibitors (and ARBs). These agents cross the placenta and can lead to fetal renal agenesis, oligohydramnios, and craniofacial malformations.
- Which antiarrhythmic is contraindicated with other QT-prolonging drugs due to torsades risk?
- Dofetilide. Additive QT prolongation heightens the risk of life-threatening ventricular arrhythmias like torsades de pointes.
- Which condition is a contraindication to combined hormonal contraception (estrogen-containing) therapy?
- History of venous thromboembolism (VTE). Estrogen components increase clotting factors, elevating the risk of recurrent thrombosis in susceptible patients.
- Which condition is a contraindication to thiazolidinediones due to fluid retention and HF worsening?
- Symptomatic heart failure (especially NYHA III–IV). Thiazolidinediones cause sodium and fluid retention, which can exacerbate congestion and decompensation in heart failure.
- Which medication is contraindicated in patients with myasthenia gravis because it worsens neuromuscular weakness?
- Aminoglycosides (for example, gentamicin). These antibiotics impair neuromuscular transmission, exacerbating muscle weakness in myasthenia gravis patients.
- Which migraine medication is contraindicated in patients with coronary artery disease?
- Triptans (for example, sumatriptan). Triptans cause coronary vasoconstriction, which can precipitate ischemia or infarction in patients with CAD.
- Which antibiotic class is generally contraindicated in pregnancy due to fetal tooth and bone effects?
- Tetracyclines. These drugs cross the placenta and incorporate into fetal tissues, leading to dental staining and impaired bone development.
- Which antibiotic is contraindicated with tizanidine due to severe hypotension and sedation risk?
- Ciprofloxacin. Ciprofloxacin inhibits CYP1A2, markedly increasing tizanidine levels and exacerbating its hypotensive and sedative effects.
- Which medication is contraindicated in patients with gastroparesis due to delayed gastric emptying?
- GLP-1 receptor agonists (for example, semaglutide). These agents further slow gastric motility, worsening symptoms and complications in patients with delayed emptying.
- Which medication is contraindicated in patients with seizure disorders because it lowers seizure threshold?
- Bupropion. Bupropion lowers the seizure threshold by blocking neuronal reuptake of dopamine and norepinephrine.
- Which antibiotic is contraindicated in infants due to risk of kernicterus from bilirubin displacement?
- Sulfonamides (for example, sulfamethoxazole). Sulfonamides displace bilirubin from albumin, increasing free bilirubin levels and risk of brain damage in neonates.
- Which condition makes nonselective beta-blockers contraindicated due to bronchospasm risk?
- Asthma or COPD with active bronchospasm. Nonselective beta-blockade antagonizes beta-2 receptors in the lungs, precipitating or worsening bronchoconstriction.
- Which condition is a contraindication to live vaccines such as MMR or varicella?
- Severe immunosuppression (for example, chemotherapy). Live vaccines can replicate uncontrollably in immunocompromised hosts, causing severe disseminated disease.
- Which antianginal is contraindicated in patients using PDE-5 inhibitors because of profound hypotension?
- Nitrates (for example, nitroglycerin). Combination causes excessive vasodilation and profound hypotension due to synergistic effects on cGMP levels.
- Which medication is contraindicated with MAO inhibitors due to risk of serotonin syndrome?
- SSRIs/SNRIs (for example, sertraline, venlafaxine). Combination inhibits serotonin metabolism, leading to excessive serotonergic activity and potentially fatal syndrome.