Dichlorphenamide
KEVEYIS
What it isCarbonic anhydrase inhibitor; primary periodic paralysis.
Why this oneIt reduces attack frequency in both hyperkalemic and hypokalemic periodic paralysis, which no other agent covers.
What limits itParaesthesia, cognitive slowing and kidney stones. It is a sulfonamide.
FDA-approved for
- periodic paralysis (2015)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Primary hyper-/hypokalemic periodic paralysis and related variants | Adults | 50 mg QD or BID | individualized | 200 mg/day |
Titration Adjust at weekly intervals (or sooner if adverse reaction).
Renal Undefined
Hepatic Contraindicated in hepatic insufficiency.
Instructions
- Evaluate response after 2 months of treatment to decide whether to continue
- Monitor serum potassium and bicarbonate at baseline and periodically
Contraindications
- Hypersensitivity to dichlorphenamide or other sulfonamides
- Concomitant use with high-dose aspirin
- Severe pulmonary disease limiting compensation to metabolic acidosis
- Hepatic insufficiency
Cautions
- Hypersensitivity / immune-mediated reactions; discontinue at first sign of rash
- Hypokalemia; monitor and correct
- Metabolic acidosis; monitor serum bicarbonate
- Falls; consider dose reduction/discontinuation
Adverse reactions
- Paresthesias
- Cognitive disorder
- Dysgeusia
- Confusional state
Pregnancy No adequate human data; teratogenic in rats; may cause fetal harm.
Lactation No data on presence in human milk or effects on the breastfed infant.
NO BOXED WARNINGS
Principal riskParaesthesia and kidney stones
Cost, est. cash$10–$500/month
Generic entry2022
Classes and tags
Clinical profile
Legacy pregnancy categoryUnknown / historical label unavailable
Defining liabilityGenerally tolerated at therapeutic doses; clinically important risks are agent-specific and increase with interactions or organ impairment.
Mechanism of action: Dichlorphenamide ballicule
Open Dichlorphenamide in the interactive console ↗
Memory aids: mascots and interaction avatars
