Aminolevulinic Acid
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Drug reference
Acetazolamide
Carbonic anhydrase inhibitor (diuretic) · Antiglaucoma agent, Antiepileptic, Prophylaxis for mountain sickness, Diuretic
START
Glaucoma 250 mg PO 2–4×/day or 500 mg SR BID; AMS 125–250 mg BID (24 h pre-ascent)
TYPICAL MAX
~1 g/day glaucoma (up to ~4 g/day IIH specialist)
STOP IF
Severe metabolic acidosis, severe electrolyte disturbance, sulfonamide hypersensitivity reaction
WATCH
Electrolytes/bicarbonate, renal function, paraesthesia, sulfonamide reactions; not for chronic angle-closure
CDSCO approvedATC S01EC01
KDIGO 2024 + manufacturer label
- ONSET
- 1h · onset (IR)
- PEAK
- 3h · Cmax (IR)
- t½
- 6h · plasma t½
- DURATION
- 10h · IR effect
EXCRETION
~90% renal unchanged; not metabolised
route + CYP
INTERACTIONS
12 major
SEVERE in our sources
PREGNANCY
Avoid in 1st trimester; later only if clearly needed (teratogenic in animals; limb defects reported)
FDA category + note
Top interactionssee all 12 →
- Aminolevulinic AcidSevereDatabaseDDInter
- AmiodaroneSevereDatabaseDDInter
- Arsenic TrioxideSevereDatabaseDDInter
- AspirinSevereDatabaseKimi deep-research + Cla
Available in India
31 branded formulations. Look up specific brands in the Drugs workspace.
Mechanism
Inhibits carbonic anhydrase reducing bicarbonate reabsorption (proximal tubule) → alkaline diuresis and metabolic acidosis; lowers aqueous humour and CSF production; alters CO2/bicarbonate buffering (altitude acclimatisation, certain epilepsies).
Indications
Glaucoma (open-angle adjunct, acute angle-closure)Acute mountain sickness prophylaxis/treatmentIdiopathic intracranial hypertensionAdjunct in certain epilepsies; oedema (rarely); urinary alkalinisation; periodic paralysis
Dosing
- Adult
- Glaucoma: 250 mg PO 1–4×/day or 500 mg SR BID. Acute mountain sickness: 125–250 mg BID (start 24 h before ascent). IIH: 250 mg–1 g/day titrated (up to 4 g). Acute glaucoma: 500 mg IV/PO then 125–250 mg q4h.
- Pediatric
- 8–30 mg/kg/day divided (indication-specific).
- Renal adjustment
- CrCl 10–50: extend interval (e.g. q12h); CrCl <10: avoid (ineffective + acidosis).
- Hepatic adjustment
- Avoid in marked hepatic disease (hepatic encephalopathy risk from alkalinisation/ammonia).
- Geriatric
- Lower dose; electrolyte/acidosis risk.
- Max dose
- ~1 g/day glaucoma; up to ~4 g/day IIH (specialist)
Pharmacokinetics
Onset
Oral ~1–1.5 h; IV ~2 min; SR ~2 h
Peak effect
1–4 h (IR); ~8–18 h (SR)
Duration
IR 8–12 h; SR 18–24 h
Half-life
~4–10 h
Bioavailability
Well absorbed (IR)
Protein binding
~90–95%
Metabolism
Not metabolised
Excretion
Renal — ~90% unchanged within 24 h (tubular secretion)
Contraindications
- Marked hepatic or renal disease/failure
- Hyperchloraemic acidosis
- Hyponatraemia/hypokalaemia, adrenal insufficiency
- Sulfonamide hypersensitivity
- Long-term use in chronic non-congestive angle-closure glaucoma
Side effects
Common
Paraesthesia (fingers/toes/peri-oral)Altered taste (carbonated drinks)PolyuriaFatigue/malaiseMild GI upset
Serious
- Metabolic acidosis (hyperchloraemic)
- Electrolyte disturbance (hypokalaemia, hyponatraemia)
- Severe sulfonamide reactions (SJS/TEN, blood dyscrasias, aplastic anaemia)
- Nephrolithiasis (calcium phosphate)
- Hepatic encephalopathy (in liver disease)
Pregnancy & lactation
Pregnancy
Avoid in 1st trimester; later only if clearly needed (teratogenic in animals; limb defects reported)
Lactation
Small amounts in milk; short-term use generally considered compatible — monitor infant
Drug interactions
Amiodarone
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Arsenic Trioxide
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Aspirin
Severe
Database
Mutual displacement + acidosis → salicylate CNS toxicity
Avoid combination; monitor
Source: Kimi deep-research + Cla
Bismuth Subsalicylate
Severe
Database
Drug interaction classified as: distribution
Source: DDInter
Choline Salicylate
Severe
Database
Drug interaction classified as: distribution
Source: DDInter
Cisapride
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Diclofenamide
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Dofetilide
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Dronedarone
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Droperidol
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Levacetylmethadol
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Related guidelines
Ask House about Acetazolamide
Continue into a citation-backed clinical answer with the drug context already attached.
Sources: KD Tripathi 7e, Goodman & Gilman 14e, Harrison 22e, Katzung·Verified: 2026-05-19 · House clinical team·Cockpit curated: 2026-05-19