Skin & Eye Infections · Medication Guide
Antibiotic Ointments in Thailand
What chloramphenicol and oxytetracycline ointments actually treat, how well they work, their side effects, and how to get them safely in Bangkok. Just as important: when a minor infection needs a doctor rather than a tube of antibiotic. Reviewed by a licensed physician at a MOPH-registered men's health clinic.
- Works in 1–2 days, if it's bacterial
- Pharmacist-controlled · use on advice
/)
Medically reviewed by Dr. Noppon Arunkajohnsak (Win)
Menscape Clinic
Last reviewed
11 July 2026
~65%
Clear without antibiotics
acute bacterial conjunctivitis, in days
1–2
Days to first improvement
if it's bacterial and responds
3–4×
Applied to the area daily
typical topical dosing schedule
5–7
Days in a usual course
continue 48 h after it clears
Key takeaways
Chloramphenicol and oxytetracycline are topical antibiotics for minor, superficial skin and eye infections — not for deep, spreading or severe ones.
Most minor bacterial eye and skin infections are self-limiting; a topical antibiotic can speed recovery, but it is not always needed.
In Thailand these are pharmacist-controlled medicines. Chloramphenicol is a dangerous drug (ยาอันตราย), and neither should be guessed at from a leftover tube.
See a doctor for eye pain, blurred vision, spreading redness, fever, or no improvement in 2–3 days — those signal something a topical won't fix.
01
What antibiotic ointments are & how they work
Antibiotic ointments are topical antibiotics applied directly to the skin or the surface of the eye to treat superficial bacterial infections. The two most common in Thai clinics and pharmacies are chloramphenicol and oxytetracycline. Both are broad-spectrum, meaning they act against a wide range of bacteria, and both are used for minor wound infections, infected grazes, and bacterial conjunctivitis.
They work by stopping bacteria from multiplying. Each blocks the bacterial machinery that builds proteins: chloramphenicol binds the bacterial 50S ribosome, while oxytetracycline, a tetracycline, binds the 30S. Applied to the surface, they reach high concentrations at the infection with very little entering the bloodstream, which is why the serious risks tied to swallowed or injected antibiotics are far less likely with short topical use.
The catch is that they only treat surface bacterial infections. They do nothing for viral or fungal problems, and most red eyes are viral while many skin rashes are irritant, allergic or fungal. They also cannot reach deep or spreading infection. That is why the useful first step is not choosing an antibiotic, but working out what you actually have.
Bacteria colonise the surface
A cut, graze or the surface of the eye is colonised by bacteria, causing redness, pus or crusting.
The ointment concentrates on-site
Applied directly, the antibiotic reaches high levels at the infection with little absorbed into the body.
Protein synthesis is blocked
Chloramphenicol binds the bacterial 50S ribosome;² oxytetracycline binds the 30S³ — both stop bacteria making the proteins they need.
Bacteria stop multiplying
Growth halts (the drugs are bacteriostatic), and your own immune system clears the infection over a few days.
02
Getting antibiotic ointments in Thailand
Thai FDA status
Both are registered in Thailand. Chloramphenicol is classified as a dangerous drug (ยาอันตราย) and is dispensed by a pharmacist. Oxytetracycline eye ointment (sold in Thailand under brands such as Terramycin) is widely stocked at pharmacies but is still a pharmacist-controlled medicine, not a free general-sale item.⁵
How Menscape handles it
A clinician first checks whether your problem is actually a bacterial infection that a topical will treat. If it is, you get the correct product and clear instructions on how and how long to use it. If it isn't, you're pointed to what will genuinely help.
Skip the drawer and the grey market
Reaching for a half-used tube, or ordering unlabelled ointment online, risks putting the wrong drug on the wrong problem — and feeds antibiotic resistance. A quick check is safer, and usually faster than guessing twice.
Thai FDA warning. The regulator has repeatedly warned against buying medicines from unlicensed online sellers. Counterfeit and substandard products are common, and nobody is accountable for what you actually receive.⁶
03
Do they work? The evidence
For genuine superficial bacterial infections, both are long-established, broad-spectrum antibiotics with decades of clinical use. The best evidence sits with bacterial conjunctivitis, where a Cochrane systematic review found the condition is largely self-limiting: about 65% of cases resolve within 2–5 days with no antibiotic at all. Antibiotics still help, modestly speeding clinical and microbiological remission — patients are roughly 1.4 times more likely to reach early remission with treatment than without.¹
The real determinant of whether these ointments work is the diagnosis, not the brand. They only help when the cause is bacterial. Most acute red eye is viral, and many skin rashes are irritant, allergic or fungal, and none of those respond to an antibiotic. Using one anyway delays the right treatment and drives resistance, which is why the honest question is not "which antibiotic" but "is this bacterial, and does it need one at all."
~65%
Clear without antibiotics
acute bacterial conjunctivitis, days 2–5
1.4×
Faster remission with antibiotics
relative benefit vs placebo
Cochrane systematic review of antibiotics for acute bacterial conjunctivitis. The benefit is real but modest, and most cases are self-limiting. Individual results vary.
04
Side effects & who shouldn't use them
Common, usually mild
Local reactions where applied: stinging, itching, redness or mild swelling. Chloramphenicol eye ointment can blur vision for a few minutes after use. With repeated or prolonged use, contact sensitivity (an allergic skin reaction) can develop, which is why courses are kept short.⁷
Rare but serious
Oxytetracycline can cause photosensitivity — treated skin burns more easily in the sun, which matters in Thailand. Chloramphenicol carries a rare risk of bone-marrow suppression, including aplastic anaemia; this is chiefly linked to systemic (oral or injected) use, not short topical courses, but it is why prolonged self-treatment is discouraged.²
Not suitable for
Anyone allergic to chloramphenicol or to tetracyclines. Newborns (chloramphenicol carries a specific neonatal risk). Pregnant or breastfeeding women and young children should use these only on a doctor's advice, and often a safer option is chosen.
Interactions & warnings
Don't combine several leftover antibiotic products, and don't extend a course to "be safe" — that is how resistance and skin sensitisation develop. Remove contact lenses during eye treatment. Tell the clinician about any history of blood disorders.
05
Alternatives & combinations
Topical · alternative antibiotic
Mupirocin or fusidic acid
Other topical antibiotics used for minor skin infections such as impetigo. A clinician may prefer one over another based on the likely bacteria and local resistance patterns.
First-line · minor wounds
Antiseptic wound care
For a simple clean cut or graze, washing with clean water and a basic antiseptic is often all that's needed. An antibiotic isn't automatic, and skipping it when it isn't needed helps slow resistance.
Prescription · when a topical isn't enough
Oral antibiotics
Spreading redness, deep wounds, animal or human bites, or any infection with fever usually needs oral antibiotics and an in-person exam. A surface ointment cannot reach those.
06
How prescription works at Menscape
/)
Not sure what you're dealing with? Book a consultation.
Message us on WhatsApp or LINE
Five minutes on your phone: describe the problem, add photos of the affected skin or eye, and your health history. It is free and PDPA-protected.
Clinician review
A licensed Thai clinician checks whether it's a bacterial infection that a topical antibiotic will actually treat, by video call or in clinic at Asoke.
Prescription, if suitable
If a topical antibiotic is right, you receive the correct product and clear instructions, dispensed by a licensed pharmacy for pickup or delivery. If it isn't, the clinician tells you what will help instead.
Follow-up
If it isn't clearly improving in 2–3 days, message the clinic. Some infections need escalation to oral antibiotics or an in-person exam, and the sooner that's caught the better.
The doctor decides. Starting a conversation is not a commitment and does not guarantee a prescription. If an antibiotic isn't the right treatment, the clinician will say so and point you to what is.
Medically reviewed by
Dr. Noppon Arunkajohnsak (Win)
Menscape Clinic, Bangkok
“Most red eyes and minor rashes aren't bacterial, so an antibiotic ointment does nothing but breed resistance. The real skill is knowing what you're actually treating — a two-minute check that's worth doing before you reach for a tube.”
- Reviewed
- 11 July 2026
- Next review
- January 2027
- Editorial standard
- Each guide is checked against the Thai FDA label and the primary literature, then reviewed by a licensed physician.
07
Frequently asked questions
Can I buy antibiotic ointment over the counter in Thailand?
Oxytetracycline eye ointment is widely available at Thai pharmacies, dispensed by the pharmacist. Chloramphenicol is a dangerous drug (ยาอันตราย) and is also pharmacist-controlled, not a free general-sale item. Neither should be used blind — a quick check that the infection is actually bacterial comes first.
How do I know if my infection is bacterial?
You often can't tell for certain just by looking. Bacterial eye infections tend to produce thick yellow-green sticky discharge, while viral ones are more watery. Skin rashes and wounds are even harder to judge, which is exactly why a clinician's check saves you from treating the wrong thing.
How long does it take to work?
If the infection is bacterial and responds, you should see improvement within 1–2 days and clearing over about 5–7 days. Keep applying for roughly 48 hours after it looks better. No improvement in 2–3 days means it's time to get it looked at.
When should I see a doctor instead of self-treating?
Eye pain, blurred or reduced vision, light sensitivity, a chemical splash, or contact-lens-related redness all need urgent eye care. For skin, spreading redness, fever, deep wounds, or animal and human bites need a proper exam, because a topical won't be enough.
Is chloramphenicol dangerous? I read about aplastic anaemia.
The rare bone-marrow risk (aplastic anaemia) is mainly linked to systemic — oral or injected — chloramphenicol, not short topical courses. It is still why courses are kept short and prolonged self-treatment is discouraged. Tell your clinician about any history of blood disorders.
Can I use an old tube of antibiotic ointment I have at home?
Better not to. It may be the wrong drug for this problem, expired, or contaminated. Eye ointments especially should never be reused between different infections or shared between people, and guessing also drives antibiotic resistance.
Can I wear contact lenses while using eye ointment?
No. Remove your lenses during treatment and until the infection has fully cleared, then ask your clinician when it's safe to resume. Wearing lenses over an active infection can worsen it and damage the lenses.
Are these safe in pregnancy or for my child?
Use them only on a clinician's advice. Chloramphenicol carries a specific newborn risk, and tetracyclines are generally avoided in pregnancy and in young children. A doctor can choose a safer alternative where one is needed.
08
References
1. Sheikh A, Hurwitz B, van Schayck CP, McLean S, Nurmatov U. Antibiotics versus placebo for acute bacterial conjunctivitis. Cochrane Database of Systematic Reviews. 2012.
2. Electronic Medicines Compendium (emc). Chloramphenicol 1% w/w Eye Ointment — Summary of Product Characteristics. Accessed 2026.
3. Chopra I, Roberts M. Tetracycline antibiotics: mode of action, applications, molecular biology, and epidemiology of bacterial resistance. Microbiol Mol Biol Rev. 2001;65(2):232-260.
4. World Health Organization. WHO Model List of Essential Medicines — chloramphenicol. WHO. 2023.
5. Thai Food and Drug Administration — drug registration database, ndi.fda.moph.go.th. Accessed 2026.
6. Thai FDA (อย.) consumer warnings on purchasing medicines from unlicensed online sellers, oryor.com. Accessed 2026.
7. British National Formulary (BNF). Chloramphenicol and Oxytetracycline monographs. NICE/BNF. Accessed 2026.
This guide is educational information, not medical advice. Chloramphenicol and oxytetracycline are pharmacist- or prescription-controlled antibiotics that should be used on the advice of a licensed clinician, who should also confirm the infection is bacterial.
This guide is part of the Menscape infection library
Book a consultationRed eye or an infected cut? Get it checked before you reach for a tube.
/)