If you inject a drug with a pH of 6.5 and pka of 8.1 into a tissue with a pH of 7.4, to what extent would you expect this drug to be ionized in the tissue?

Correct Answer: A

Rationale: The percentage of ionization of a weak acid or base can be estimated using the Henderson-Hasselbalch equation:

Correct Answer: D

Rationale: Enteric-coated tablets should not be crushed or opened, as this disrupts their protective coating and can cause gastric irritation. The patient should be instructed to swallow the tablets whole with plenty of water or milk. Crushing (A) or opening the tablets (C) is inappropriate. Notifying the healthcare provider (B) may be necessary if the patient cannot tolerate the medication.

Correct Answer: C

Rationale: Sporotrichosis, from Sporothrix schenckii, requires antifungals like itraconazole. Option , inhibiting lanosterol to ergosterol conversion, is correct-itraconazole blocks 14-α-demethylase, disrupting fungal membrane synthesis. Option , pore formation, is amphotericin B's mechanism. Option , microtubule disruption, is griseofulvin's. Option , squalene monooxygenase inhibition, is terbinafine's. Option (E), 5-FU conversion, is flucytosine's. Itraconazole's ergosterol inhibition effectively treats this subcutaneous infection, targeting fungal viability.

Correct Answer: A

Rationale: Dalfampridine treats MS by blocking potassium channels in demyelinated axons, enhancing nerve conduction and improving walking ability. Exposed potassium channels in MS leak current, impairing signal propagation; dalfampridine's blockade restores function. Donepezil boosts acetylcholine for Alzheimer's. Riluzole reduces glutamate in ALS. Bromocriptine, a dopamine agonist, manages Parkinson's. Dalfampridine's unique potassium channel action directly addresses MS's neurological deficit, supported by clinical evidence, making it the correct agent here.

Correct Answer: C

Rationale: A common side effect of Heparin, which is an anticoagulant medication, is the risk of bleeding. Heparin works by preventing the formation of blood clots, which can lead to a bleeding risk as it inhibits the normal clotting process. Patients taking Heparin should be monitored closely for signs of bleeding, such as easy bruising, prolonged bleeding from minor cuts, or blood in the urine or stools. It is important for healthcare providers to closely monitor patients on Heparin therapy and adjust the dosage as needed to minimize the risk of excessive bleeding.