Are isotretinoin and tretinoin the same drug?

They are different molecules, both retinoids and both derived from vitamin A, with separate FDA approvals. One is taken by mouth and one is applied to the skin, and their labels cover different severities of acne.

Is the oral one stronger?

The labels do not rank them, and they were not studied against each other. What the isotretinoin label does state is that it is reserved for severe nodular acne unresponsive to conventional therapy, which is a statement about where it sits in treatment rather than about strength.

Retin-A Micro lists no contraindications. Does that make it safer?

A short contraindications section is not a safety score. It means the label names no group for whom the product must not be used; warnings, precautions and adverse reactions are recorded in their own sections, and the full lists from both labels are reproduced on the individual pages.

Comparison

Isotretinoin vs tretinoin

Isotretinoin capsules

ISOTRETINOIN

Approved for skin

Upsher-Smith Laboratories, LLCLabel version 4, effective 13 February 2026

Retin-A Micro

TRETINOIN

Approved for skin

Bausch Health US LLCLabel version 23, effective 1 September 2025

Each stripe is one section of the label, each division in a stripe one entry in that section. The red bar marks a boxed warning.

Isotretinoin and tretinoin are both retinoids and both approved for acne, which is where the similarity stops. One is a capsule taken for a fixed course, the other a gel applied to the skin. Their labels do not describe the same patient, and they do not carry the same warnings.

Side by side, straight from the labels

From the FDA label

This table is generated from the two source labels, not typed out by hand, so it cannot drift from what the regulator approved.

Label section	Isotretinoin capsulesISOTRETINOIN	Retin-A MicroTRETINOIN
Active ingredient	IsotretinoinOral retinoid	TretinoinTopical retinoid
Supply	Prescription	Prescription
What pharmacies payAcquisition cost, not retail	$38.05 per tablet, capsule or pen, brand	$1.02 per gram, generic
Boxed warning	WARNING: EMBRYO-FETAL TOXICITY	None
What the FDA approved it for	Isotretinoin capsules are indicated for the treatment of severe recalcitrant nodular acne in non-pregnant patients 12 years of age and older with multiple inflammatory nodules with a diameter of 5 mm or greater. Because of significant adverse reactions associated with its use, isotretinoin capsules are reserved for patients with severe nodular acne who are unresponsive to conventional therapy, including systemic antibiotics. Isotretinoin capsules are retinoids indicated for the treatment of severe recalcitrant nodular acne in non-pregnant patients 12 years of age and older with multiple inflammatory nodules with a diameter of 5 mm or greater.	RETIN-A MICRO ® is indicated for the topical treatment of acne vulgaris in adults and pediatric patients 12 years of age and older. RETIN-A MICRO is a retinoid indicated for the topical treatment of acne vulgaris in adults and pediatric patients 12 years of age and older.
Forms and strengths	Isotretinoin capsules, USP are available in 10 mg, 20 mg and 30 mg. 10 mg: Yellow, oblong, opaque, soft gelatin capsule, containing a yellow/orange viscous liquid, imprinted "570" in black ink. Capsules: 10 mg, 20 mg and 30 mg	0.1% (1 mg of tretinoin per gram). Gel: 0.04%, 0.06%, 0.08%, and 0.1%
How the label says it is taken	Recommended dosage for isotretinoin capsules is 0.5 to 1 mg/kg/day given in two divided doses without regard to meals for 15 to 20 weeks Adult patients with very severe disease (scarring, trunk involvement) may increase dosage to 2 mg/kg/day of isotretinoin capsules in divided doses. Once daily dosing is not recommended. If a dose of isotretinoin capsules is missed, just skip that dose. Do not take two doses of isotretinoin capsules at the same time. Perform pregnancy tests prior to prescribing, each month during therapy, end of therapy, and one month after discontinuation. Prior to prescribing, perform fasting lipid profile and liver function tests.	For topical use only. Not for oral, ophthalmic, or intravaginal use. Keep away from eyes, mouth, paranasal creases of the nose, and mucous membranes. Apply a thin layer of RETIN-A MICRO to skin where acne lesions appear (cover the entire affected area) (0.04%, 0.06%, 0.08%, or 0.1%) once daily in the evening.
Most common adverse reactions	Most common adverse reactions (incidence ≥ 5%) are: dry lips, dry skin, back pain, dry eye, arthralgia, epistaxis, headache, nasopharyngitis, chapped lips, dermatitis, increased creatine kinase, cheilitis, musculoskeletal discomfort, upper respiratory tract infection, reduced visual acuity.	Most common adverse reactions were skin irritation, skin burning, erythema, peeling, dryness, itching, and dermatitis.
Warnings and precautions	Psychiatric Disorders (depression, psychosis, suicidal thoughts and behavior, and aggressive and/or violent behaviors): Prior to and during therapy assess for these conditions; stop if these conditions occur on therapy Intracranial Hypertension (Pseudotumor Cerebri): Avoid use with concomitant tetracyclines Serious Skin Reactions: Monitor for Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and other serious skin reactions Acute Pancreatitis: If occurs, discontinue treatment Lipid Abnormalities (hypertriglyceridemia, low HDL, and elevation of cholesterol): Monitor lipid levels at regular intervals; stop if hypertriglyceridemia cannot be controlled Hearing Impairment: Discontinue and refer to specialized care Hepatotoxicity: Monitor liver function tests prior to and during therapy Inflammatory Bowel Disease: Discontinue for abdominal pain, rectal bleeding, or severe diarrhea	Local Skin Irritation: RETIN-A MICRO can cause local skin irritation, including excessive dryness, redness, swelling, peeling, itching, blistering, burning, or stinging Initial Worsening of Inflammatory Acne Vulgaris: During the early weeks of RETIN-A MICRO treatment, an apparent exacerbation of inflammatory lesions may occur. If RETIN-A MICRO is tolerated, this should not be considered a reason to discontinue therapy. Photosensitivity: RETIN-A MICRO can cause photosensitivity. Advise patients to avoid or minimize unnecessary exposure to UV light, including sunlight and sunlamps. Advise patients to use sunscreen (SPF ≥15) and sun-protective clothing if UV light exposure cannot be avoided. Avoid use on sunburn skin.
Contraindications	Hypersensitivity to this product or any of its components	None. The label states that there are no contraindications.
Drug interactions	Vitamin A: may cause additive adverse reactions Tetracyclines: avoid concomitant use	-
Label version	13 February 2026	1 September 2025

The approved severities are not the same

Written by us

The Retin-A Micro label covers the topical treatment of acne vulgaris in adults and paediatric patients 12 years of age and older. The isotretinoin label is narrower: severe recalcitrant nodular acne in non-pregnant patients 12 years and older with multiple inflammatory nodules.

The isotretinoin label goes further and states why it is written that way. Because of the significant adverse reactions associated with its use, it says, isotretinoin is reserved for patients with severe nodular acne who are unresponsive to conventional therapy. That sentence is a restriction, not a description, and it has no counterpart in the topical label.

One is a course, the other is an application

Written by us

Isotretinoin is dosed by body weight in two divided doses daily for a set number of weeks, and its label states that once daily dosing is not recommended. Retin-A Micro is applied as a thin layer to the affected area once a day, and its label states that it is for topical use only, not for oral, ophthalmic or intravaginal use.

The exact strengths and the dosing figures are in the table above, taken from each label.

The warnings sit in different places, and counting them misleads

Written by us

Isotretinoin carries a boxed warning about embryo-fetal toxicity. Retin-A Micro carries no boxed warning at all.

Look at the contraindications and you get the opposite impression: the Retin-A Micro label states that there are none, and the isotretinoin label lists only hypersensitivity to the product or its components. Read as a count, that makes the two look comparable. They are not, and this is a good illustration of why the number of entries in a section says nothing on its own. The pregnancy restriction that dominates isotretinoin sits in the boxed warning and in the indication itself, not in the contraindications list.

The reported side effects are local in one case and not in the other

Written by us

The most common adverse reactions in the Retin-A Micro label are all at the site of application: skin irritation, burning, redness, peeling, dryness, itching and dermatitis. The isotretinoin list reaches well beyond the skin, adding back pain, joint pain, dry eye, nosebleeds, headache and nasopharyngitis alongside the dry lips and dry skin.

That difference follows from the route rather than from potency. A medicine swallowed reaches tissues a cream does not.

What this page does not tell you

Written by us

It does not say which one a person should use, and the difference in approved severity is not an invitation to self-select. Isotretinoin prescribing in the United States is tied to a risk management programme, and both products are decisions for a clinician who knows the person's history.

Common questions

Written by us

Are isotretinoin and tretinoin the same drug?: They are different molecules, both retinoids and both derived from vitamin A, with separate FDA approvals. One is taken by mouth and one is applied to the skin, and their labels cover different severities of acne.
Is the oral one stronger?: The labels do not rank them, and they were not studied against each other. What the isotretinoin label does state is that it is reserved for severe nodular acne unresponsive to conventional therapy, which is a statement about where it sits in treatment rather than about strength.
Retin-A Micro lists no contraindications. Does that make it safer?: A short contraindications section is not a safety score. It means the label names no group for whom the product must not be used; warnings, precautions and adverse reactions are recorded in their own sections, and the full lists from both labels are reproduced on the individual pages.

Sources

Every fact above comes from one of these documents. The date is the effective date of the label version this page was built from.

FDA prescribing information for Isotretinoin capsules
Upsher-Smith Laboratories, LLC. Label version 4, effective 13 February 2026.
Full label on DailyMed Approval record ANDA212333
FDA prescribing information for Retin-A Micro
Bausch Health US LLC. Label version 23, effective 1 September 2025.
Full label on DailyMed Approval record NDA020475

Other comparisons in this category

Page last updated: 8 August 2026

Compiled by the HealthyStudy editorial team from FDA source documents. No medical reviewer is credited on this page, because none reviewed it.