Carbonic Anhydrase Inhibitors

The carbonic anhydrase inhibitors are considered:

Relatively mild

Available agents include:

Acetazolamide

Dichlorphenamide (Keveyis)

Methazolamide

The enzyme carbonic anhydrase is a catalyst for:

The formation of sodium bicarbonate

Most often, carbonic anhydrase inhibitors are used to treat?

Glaucoma

How does CAI treat glaucoma?

By inhibiting Carbonic anhydrase, doing so results in decreased secretion of aqueous humor of the eye.

Acetazolamide is available only in?

• Orally

• Sustained orally

• IV

Contraindications?

Allergies

Chronic non-congestive angle-closure glaucoma

Pregnancy

Adverse effects

• Metabolic acidosis

• Hypokalemia

• Paresthesia

• Confusion

• Drowsiness

Clinically Important Drug–Drug Interactions

Salicylates – increased risk of toxicity

Medications causing metabolic acidosis

Potassium-lowering drugs

Acetazolamide oral route:

1. Onset?

2. Peak?

3. Duration?

1. 1 Hour

2. 2-4 Hours

3. 6-12 Hours

Acetazolamide Sustained-release oral route:

1. Onset?

2. Peak?

3. Duration?

1. 2 Hours

2. 8-12 Hours

3. 18-24 Hours

Acetazolamide IV route:

1. Onset?

2. Peak?

3. Duration?

1. 1-2 Minutes

2. 15-18 Minutes

3. 4-5 Hours