Calcium channel blockers

Question 1

Dihydropyridine drugs (-ipine)

Answer 1

Nifedipine (procardia)
Isradipine (DynaCirc)
Felodipine (plendil)
Amlodipine (Norvasc)
Nisoldipine (sular)
Nimodipine (nimotop)
Nicardipine (cardene)
Clecidipine (cleviprex) - Short acting DHP, metabolized quickly by esterases

Question 2

Dihydropyridines MOA

Answer 2

More potent in relaxing smooth muscle
Voltage dependence - a more elevated resting membrane is preferred for the DPHs so this is why we see a stronger selectivity to the vascular when using DHPs
- DHPs do not bind directly to the poor, they bind allosterically and will bind to the closed channel and prevent opening
- SE ankle edema, facial flushing, tachycardia

Question 3

Phenylalkylamine

Answer 3

Verapamil (calan, Isoptin)

Question 4

Verapamil MOA

Answer 4

• Causes Vasodilation but less potent than DHPS
• Reflex tachycardia is blunted
• Inhibitory effects on the heart is due to frequency-dependent block
• Binds in the pore and blocks Ca Influx

SE ankle edema, constipation

Question 5

Benzothiazepine

Answer 5

Diltiazem (Cardizem)

Question 6

Diltiazem

Answer 6

Directly inhibits the heart less than verapamil but more than DHPS
frequency-dependent block of ca channels
- SE ankle edema, dizziness

Question 7

Clinical application of these drugs

Answer 7

angina pectoris, arrhythmia, hypertension