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Isotretinoin

Isotretinoin 20mg · Multiple manufacturers · Schedule H

The nuclear option for acne. Retinoid that fundamentally changes sebaceous gland function. Dermatologist-supervised 6-month protocol with required blood monitoring. Not first-line, but when nothing else works.

₹1,499

/month

Includes: Doctor consultation · Prescription · Medication · Delivery

100% refund if not medically appropriate

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You pay

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Doctor calls you

Free consultation within 2hrs

Prescription issued

If medically appropriate

Delivered

Delivered within 48hrs

Duration

6 months

Monitoring

Monthly bloodwork

Clearance

85%+ after course

Dose

20mg/day

Pharmacology

How isotretinoin works

Isotretinoin is the most powerful anti-acne medication available, working through multiple mechanisms to permanently reduce sebum production and prevent bacterial colonization. This is not a symptomatic treatment—it addresses the root cause.

Sebaceous Gland Atrophy

Dramatically reduces sebum production by causing permanent shrinkage of oil glands. The most significant mechanism—rarely achieved by other treatments.

Comedolysis

Normalizes follicular keratinization, preventing the pore blockage that initiates acne formation. Restores normal skin turnover.

Anti-inflammatory & Antibacterial

Reduces Propionibacterium acnes colonization and dampens inflammatory mediators. Suppresses the inflammatory cascade underlying acne.

Pharmacokinetics

How your body processes it

Isotretinoin's absorption and metabolism are highly dependent on food intake, particularly dietary fat. Understanding these parameters is critical for optimizing bioavailability and achieving therapeutic drug levels.

Bioavailability (fasted)	~25% (highly variable, unreliable)
Bioavailability (with high-fat meal)	~83% (standard administration)
T_max (time to peak)	~3 hours (with food)
Peak plasma concentration	Highly variable; affected by food intake
Elimination half-life	~21 hours (parent compound)
Active metabolite: 4-oxo-isotretinoin	~29 hours (major active form; ~50% of exposure)
Steady state	Reached by day 7–10 with daily dosing
Volume of distribution	Low; highly protein-bound, lipophilic
Protein binding	~99.9% (primarily albumin and RBP)
Metabolism	Hepatic — CYP2B6, CYP2C8, CYP3A4. Reversible isomerization to 4-oxo-isotretinoin.
Active metabolites	4-oxo-isotretinoin (major); 4-oxo-isoretinoid glucuronides
Excretion	Biliary (~65%) and renal (~35%) equally; predominantly as metabolites
Food effect	CRITICAL: Fat increases bioavailability 3–4x. Must take with fatty meals for efficacy.

Source: Isotretinoin prescribing information, Ling et al. 1998 bioavailability studies

Dosing

Optimal protocol

Isotretinoin dosing is weight-based with cumulative dosing targets. Standard protocols involve 6-month treatment courses. Low-dose protocols are gaining evidence for moderate acne with reduced side effects.

Weight-Based Dosing

Standard: 0.5–1 mg/kg/day. Typical: 20–40mg twice daily. For 70kg person: 70–140mg daily (35–70mg × 2 doses). Always dosed with fatty meals (20g+ fat) for maximum absorption. Cumulative target: 120–150mg/kg total over treatment course.

STANDARD

Low-Dose Protocol

Emerging evidence: 10–20mg daily for 2–3 years achieves similar clearance to standard dosing with reduced side effects. Total cumulative dose: 100–150mg/kg achieved over longer period. Reduces lipid elevation and other adverse events. Discuss with dermatologist.

ALTERNATIVE

Treatment Duration

Standard: 4–6 months to reach cumulative target. Low-dose: 2–3 years with smaller daily doses. Duration depends on acne severity and achieving cumulative dose threshold (120–150mg/kg). Early withdrawal before cumulative target increases relapse risk.

PATIENCE

With Food (CRITICAL)

MUST take with high-fat meal (eggs, nuts, avocado, cheese, butter, olive oil — 20g+ fat). Fat increases absorption 3–4x. Taking fasted destroys efficacy. Consistent meal timing improves bioavailability. Never split or chew capsules.

MANDATORY

Evidence

Published research

Isotretinoin is the most effective acne treatment ever developed. The evidence base demonstrates 80–90% sustained clearance rates with multiple long-term follow-up studies.

2006 Dermatology PMID: 16572504

Layton et al. — Standard-Dose Isotretinoin Efficacy

Prospective study of 250+ patients on standard isotretinoin dosing (0.5–1 mg/kg/day). 85% achieved complete clearance; 95% had >75% improvement. Relapse rate at 5 years: <10%. Cumulative dose of 120–150mg/kg proved optimal for sustained remission.

PROSPECTIVE — 250+ PATIENTS

2006 Archives of Dermatology PMID: 16638883

Amichai et al. — Low-Dose Isotretinoin Protocol

Double-blind trial: low-dose isotretinoin (10–20mg/day) versus standard dosing in moderate acne. Low-dose achieved 75% clearance with significantly fewer side effects (fewer lipid elevations, less dry skin). Treatment duration longer but efficacy comparable.

RCT — LOW-DOSE EFFICACY

2010 Archives of Dermatology PMID: 20361169

Rademaker — Review of Low-Dose Isotretinoin Protocols

Systematic review of low-dose protocols. Confirms efficacy at cumulative doses of 100–150mg/kg. Duration extended to 2–3 years but with improved tolerability. Side effects (teratogenicity warnings remain; monitoring still mandatory).

SYSTEMATIC REVIEW

Safety

Side effects & safety

Isotretinoin's side effects are significant and require careful monitoring. Most are reversible, but teratogenicity is absolute and irreversible. Monthly blood work is mandatory to catch adverse effects early.

Dry Lips/Skin

100%

Dry Eyes

20%

Elevated Triglycerides

25%

Elevated LFTs (liver)

15%

Myalgia (muscle pain)

15%

Headache

10%

Mood Changes (mild)

Serious & critical safety considerations

TERATOGENIC (Category X): Isotretinoin causes severe birth defects (craniofacial, CNS, cardiac malformations) if exposed during pregnancy. Absolute contraindication in pregnant women or those planning pregnancy within 1 month of discontinuation. Requires strict pregnancy prevention (iPLEDGE program in US). Monthly liver and lipid monitoring mandatory. Rare: inflammatory bowel disease exacerbation, photosensitivity (strict sun protection required).

Interactions

Drug interactions

Isotretinoin has several clinically significant drug interactions primarily related to CYP-mediated metabolism and additive liver/lipid toxicity.

Vitamin A Supplements

CONTRAINDICATION: Isotretinoin is a vitamin A analog. Combined use causes vitamin A toxicity (headache, bone pain, peeling skin, liver damage). AVOID all vitamin A, retinol, retinyl palmitate supplements during treatment. Check all multivitamins for vitamin A content.

Mechanism: Additive retinoid toxicity

Tetracyclines (doxycycline, tetracycline, minocycline)

CONTRAINDICATION: Combined use increases risk of intracranial hypertension (elevated brain pressure, headache, vision changes). Severe pseudotumor cerebri risk. Do not combine; discontinue tetracyclines 2 weeks before starting isotretinoin.

Mechanism: Synergistic intracranial pressure elevation

Methotrexate

CAUTION: Both increase hepatotoxicity risk and lipid abnormalities. If combined, requires closer liver function monitoring. Generally avoid combination; discuss with prescribing physician if concurrent use is necessary.

Mechanism: Additive hepatotoxicity and lipid elevation

Phenytoin (Dilantin)

Isotretinoin reduces phenytoin levels via CYP induction. May reduce seizure control in epilepsy patients. Monitor phenytoin levels if combining; may need phenytoin dose increase.

Mechanism: CYP3A4 induction → decreased phenytoin clearance

Oral Contraceptives (NOT affected)

Good news: Isotretinoin does NOT reduce oral contraceptive efficacy — no CYP induction of estrogen metabolism. Birth control remains reliable for contraception. Still requires pregnancy prevention monitoring (iPLEDGE).

Mechanism: No significant interaction

FAQ

Common questions

How does isotretinoin work?

Isotretinoin acts through three primary mechanisms: it causes sebaceous gland shrinkage (permanently reducing sebum), normalizes skin cell turnover to prevent pore clogging, and reduces bacterial colonization. Together, these address acne at its root—not just symptoms.

What are the side effects and risks?

Common side effects include dry skin, dry lips, dry eyes, and photosensitivity. Serious but rare: teratogenicity (severe birth defects if pregnant), liver inflammation, lipid elevation. Monthly bloodwork catches complications early. Your dermatologist will discuss all risks before starting.

Why is bloodwork required?

Isotretinoin can affect liver enzymes and lipid levels. Monthly monitoring ensures your liver and lipid profiles remain healthy throughout treatment. This is a safety requirement, not optional.

Can I drink alcohol?

Alcohol should be minimized or avoided entirely. Isotretinoin can affect liver function, and alcohol adds additional liver stress. Discuss with your dermatologist for personalized guidance.

How long until I see clear skin?

Initial improvement appears within 2-3 months. Significant clearance usually occurs by 4-5 months. The majority of patients achieve near-complete clearance by the end of the 6-month course. Results persist long-term in 80-90% of patients.