Desogestrel
Severe
Textbook-cited
Contraceptive failure
Advise alternative contraception
Source: KDT 7e · p949
Drug reference
Minocycline
Tetracycline antibacterial agent (semi-synthetic) · Antibiotic
Also known as Minocycline Hydrochloride, Dynacin, Minocin, Solodyn, Arestin
START
Rule out pregnancy; verify age >8 years. Counsel on photosensitivity, dizziness (vestibular), and skin discoloration risk. Take with full glass of water; remain upright 30 minutes (esophagitis risk).
TYPICAL MAX
200mg/day for chronic use. Higher doses for short courses only. Skin hyperpigmentation risk increases with duration >3-6 months.
STOP IF
Severe headache with papilledema (pseudotumor cerebri), severe dizziness/vertigo, jaundice, SLE-like syndrome, severe rash, C. difficile diarrhea.
WATCH
Dizziness/vertigo is common and dose-limiting—more frequent in women. Skin hyperpigmentation (blue-gray) can be permanent, especially in acne scars and sun-exposed areas. Photosensitivity—sun protection essential. Autoimmune hepatitis and DRESS have been reported—monitor LFTs with long-term use.
CDSCO approvedSchedule HATC J01AA08
KDIGO 2024 + manufacturer label
- ONSET
- 30min · Onset ~30 min
- PEAK
- 2.5h · Tmax 1-4 hours
- t½
- 17h · t½ ~11-23 hours
- DURATION
- 12h · 12 hours (BID)
EXCRETION
Fecal and hepatic metabolism (~90%)
route + CYP
INTERACTIONS
12 major
SEVERE in our sources
PREGNANCY
Avoid in 2nd and 3rd trimesters—causes permanent yellow-brown tooth discoloration and bone growth inhibition in fetus. First trimester: use only if essential. Crosses placenta.
FDA category + note
Top interactionssee all 12 →
- DesogestrelSevereTextbook-citedKDT 7e · p949
- EthinylestradiolSevereTextbook-citedKDT 7e · p949
- FurosemideSevereTextbook-citedKDT 7e · p949
- LevonorgestrelSevereTextbook-citedKDT 7e · p949
Available in India
83 branded formulations. Look up specific brands in the Drugs workspace.
Mechanism
Binds to 30S ribosomal subunit, inhibiting bacterial protein synthesis by blocking aminoacyl-tRNA attachment to mRNA-ribosome complex. Bacteriostatic. Broader spectrum than tetracycline; effective against some tetracycline-resistant organisms. Lipophilic—excellent tissue penetration including CNS and skin.
Indications
Acne vulgaris (moderate to severe)RosaceaCommunity-acquired MRSA skin infectionsRocky Mountain spotted fever and other rickettsial diseasesMeningococcal carrier state eradicationMycobacterium marinum infectionsPeriodontitis (local delivery)Rheumatoid arthritis (DMARD—off-label, limited evidence)
Dosing
- Adult
- Acne/rosacea: 50-100mg PO BID or 100mg daily (extended-release). Bacterial infections: 200mg loading, then 100mg BID. MRSA: 100mg BID x 7-14 days. Meningococcal carrier: 100mg BID x 5 days.
- Pediatric
- >8 years: 4mg/kg loading, then 2mg/kg BID (max 100mg/dose).
- Renal adjustment
- No adjustment needed (hepatically metabolized, not renally excreted like other tetracyclines).
- Hepatic adjustment
- Use caution; avoid in severe hepatic impairment.
- Geriatric
- No specific adjustment; increased vestibular toxicity risk; monitor for dizziness.
- Max dose
- 200mg/day (most indications); 400mg/day (short courses for severe infections)
Pharmacokinetics
Onset
Antibacterial effect within 24-48 hours; acne improvement 4-8 weeks
Peak effect
Tmax 1-4 hours; ER: 3.5-4 hours; steady-state in 3-5 days
Duration
12 hours (BID dosing)
Half-life
~11-23 hours (longer than tetracycline)
Bioavailability
~90-100% (food and dairy reduce by ~20%)
Protein binding
~70-75%
Metabolism
Extensive hepatic metabolism to active and inactive metabolites (unlike other tetracyclines)
Excretion
~10% unchanged in urine; ~30-40% fecal (metabolites and unchanged); remainder metabolized
Contraindications
- Hypersensitivity to tetracyclines
- Pregnancy (second and third trimesters—fetal bone and tooth discoloration)
- Children <8 years (tooth enamel hypoplasia and discoloration)
- Severe hepatic impairment
- Systemic lupus erythematosus (may exacerbate)
Side effects
Common
Dizziness / vertigo (vestibular toxicity—dose-related, reversible)Nausea and vomitingPhotosensitivitySkin hyperpigmentation (blue-gray, dose- and duration-dependent, may be permanent)Diarrhea
Serious
- Hepatotoxicity (autoimmune hepatitis, DRESS)
- Pseudotumor cerebri (benign intracranial hypertension)
- Systemic lupus erythematosus exacerbation or drug-induced lupus
- Severe cutaneous adverse reactions (SJS/TEN)
- Clostridioides difficile colitis
- Permanent tooth discoloration (children)
- Vestibular toxicity (persistent)
Pregnancy & lactation
Pregnancy
Avoid in 2nd and 3rd trimesters—causes permanent yellow-brown tooth discoloration and bone growth inhibition in fetus. First trimester: use only if essential. Crosses placenta.
Lactation
Excreted in breast milk; may cause tooth discoloration in nursing infants. Use short courses if necessary; avoid prolonged use during breastfeeding.
Drug interactions
Ethinylestradiol
Severe
Textbook-cited
Contraceptive failure
Advise alternative contraception
Source: KDT 7e · p949
Furosemide
Severe
Textbook-cited
Severe vestibular toxicity (vertigo, dizziness).
Avoid concurrent use
Source: KDT 7e · p949
Levonorgestrel
Severe
Textbook-cited
Contraceptive failure
Advise alternative contraception
Source: KDT 7e · p949
Lithium
Severe
Textbook-cited
Lithium toxicity
Avoid tetracycline or monitor lithium levels and reduce dose
Source: KDT 7e · p949
Norethisterone
Severe
Textbook-cited
Contraceptive failure
Advise alternative contraception
Source: KDT 7e · p949
Acitretin
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Aminolevulinic Acid
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Leflunomide
Severe
Database
Clinical effect not specified
Source: DDInter
Lomitapide
Severe
Database
Clinical effect not specified
Source: DDInter
Methoxyflurane
Severe
Database
Clinical effect not specified
Source: DDInter
Mipomersen
Severe
Database
Clinical effect not specified
Source: DDInter
Related guidelines
Ask House about Minocycline
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