What You Should Know About Ofloxacin Side Effects

Every medication comes with potential side effects, and Ofloxacin is no exception. As a fluoroquinolone antibiotic, Ofloxacin is effective against a wide range of bacterial infections — but it also carries some serious risks that the FDA wants you to know about.

This guide breaks down the common side effects you might experience, the serious ones to watch for, and exactly when you should call your doctor or seek emergency care.

What Is Ofloxacin?

Ofloxacin is a fluoroquinolone antibiotic available in three forms: oral tablets (200 mg, 300 mg, 400 mg), ophthalmic solution (0.3%), and otic solution (0.3%). It's used to treat urinary tract infections, respiratory infections, skin infections, ear infections, and eye infections. The brand names Floxin and Ocuflox have been discontinued, but generic Ofloxacin remains widely available.

For a deeper look at how this medication works in your body, see our guide on Ofloxacin's mechanism of action.

Common Side Effects

Most people who take Ofloxacin will experience mild side effects — or none at all. These are the most frequently reported, based on FDA labeling and clinical trials:

• Nausea — The most common complaint. Taking Ofloxacin with food may help, though it can be taken on an empty stomach.
• Diarrhea — Mild and usually self-limiting. Stay hydrated and contact your doctor if it becomes severe or bloody.
• Headache — Typically mild and manageable with over-the-counter pain relievers (avoid NSAIDs if possible — see drug interactions).
• Dizziness — May affect your ability to drive or operate machinery. Be careful until you know how the medication affects you.
• Insomnia — Some patients have trouble sleeping. Taking your dose earlier in the day may help.
• Vomiting — Less common than nausea but can occur, especially at higher doses.
• Abdominal pain — Mild stomach discomfort that usually resolves on its own.
• Vaginal discharge — Reported in some women taking oral Ofloxacin, likely related to changes in normal bacterial flora.
• Rash — Mild skin rash can occur. If it worsens or is accompanied by other symptoms, contact your doctor.

These side effects are generally mild and go away on their own as your body adjusts to the medication. If any of them become bothersome or don't improve, talk to your doctor.

Serious Side Effects — FDA Boxed Warning

Ofloxacin carries an FDA boxed warning — the most serious type of safety warning. This applies to all fluoroquinolone antibiotics and covers three major risks:

Tendinitis and Tendon Rupture

Fluoroquinolones can damage tendons, most commonly the Achilles tendon. This can happen during treatment or even weeks after stopping the medication. The risk is higher if you:

• Are over 60 years old
• Take corticosteroids (like Prednisone)
• Have had a kidney, heart, or lung transplant

What to watch for: Pain, swelling, or tenderness in your tendons (especially the back of the ankle). If you notice these symptoms, stop taking Ofloxacin and call your doctor immediately. Rest the affected area and avoid exercise until evaluated.

Peripheral Neuropathy

Ofloxacin can cause nerve damage in your hands and feet that may be permanent. This can start during treatment or shortly after.

What to watch for: Tingling, numbness, burning, or pain in your hands or feet. Weakness in your arms or legs. If you experience any nerve-related symptoms, stop taking the medication and contact your doctor right away.

Central Nervous System (CNS) Effects

In rare cases, fluoroquinolones can cause serious CNS effects including seizures, psychosis, anxiety, confusion, hallucinations, and increased intracranial pressure.

What to watch for: Unusual changes in mood or behavior, confusion, tremors, seizures, or severe headaches. Seek emergency care if you experience any of these.

Other Serious Side Effects

Beyond the boxed warning, Ofloxacin can also cause:

• QT prolongation — An abnormal heart rhythm that can be life-threatening. Risk increases if you take other QT-prolonging medications like Amiodarone or Sotalol.
• Severe allergic reactions (anaphylaxis) — Difficulty breathing, hives, swelling of the face or throat. Call 911 immediately.
• Clostridioides difficile (C. diff) diarrhea — Severe, watery diarrhea that can be life-threatening. Can occur during treatment or weeks afterward.
• Severe hypoglycemia — Dangerously low blood sugar, especially in diabetic patients taking Insulin or Sulfonylureas.
• Aortic aneurysm and dissection — Rare but serious. Seek emergency care for sudden severe chest, stomach, or back pain.
• Photosensitivity — Increased sensitivity to sunlight. Use sunscreen and avoid prolonged sun exposure.
• Liver damage (hepatotoxicity) — Yellowing of the skin or eyes, dark urine, severe fatigue. Contact your doctor immediately.

Side Effects in Specific Populations

Pregnant and Breastfeeding Women

Ofloxacin is Category C in pregnancy — meaning animal studies have shown risks but there aren't enough human studies. It should generally be avoided during pregnancy and breastfeeding. Talk to your OB/GYN about safer alternatives.

Children

Oral Ofloxacin is not recommended for children under 18 due to the risk of musculoskeletal problems, including damage to developing cartilage and joints. The otic (ear drop) formulation is approved for children 1 year and older.

Older Adults

Patients over 60 face a higher risk of tendon rupture, especially if also taking corticosteroids. Dose adjustments may be needed for those with reduced kidney function.

Patients with Myasthenia Gravis

Ofloxacin is contraindicated in patients with myasthenia gravis, as it can worsen muscle weakness and cause life-threatening breathing problems.

How to Manage Common Side Effects

If you're experiencing mild side effects, here are some practical tips:

• Nausea or stomach upset — Try taking Ofloxacin with a light meal. Avoid spicy or greasy foods.
• Diarrhea — Stay hydrated with water and electrolyte drinks. Probiotics may help restore gut bacteria, but take them at least 2 hours apart from your antibiotic dose.
• Dizziness — Get up slowly from sitting or lying positions. Avoid driving until the dizziness passes.
• Insomnia — Take your doses earlier in the day if your schedule allows. Avoid caffeine close to bedtime.
• Photosensitivity — Wear sunscreen (SPF 30+), protective clothing, and sunglasses. Avoid tanning beds.

Never stop taking your antibiotic early just because of mild side effects. If you can't tolerate the medication, call your doctor — they can switch you to an alternative antibiotic.

When to Call Your Doctor

Contact your doctor if you experience:

• Tendon pain, swelling, or weakness
• Tingling, numbness, or burning in your hands or feet
• Severe or bloody diarrhea
• Signs of an allergic reaction (rash, hives, difficulty breathing)
• Yellowing of skin or eyes
• Unusual mood changes, confusion, or hallucinations
• Irregular heartbeat or fainting

Call 911 or go to the ER if you have difficulty breathing, chest pain, severe swelling, seizures, or signs of a severe allergic reaction.

Final Thoughts

Most people tolerate Ofloxacin well, and serious side effects are uncommon. But because of the FDA boxed warning, it's important to be informed about what to watch for — especially tendon problems, nerve damage, and CNS effects.

The key is knowing the difference between a mild, expected side effect (like nausea) and a serious warning sign (like tendon pain or numbness in your feet). When in doubt, call your doctor. It's always better to check than to wait.

If you're looking for Ofloxacin at a good price, check out our guide on saving money on Ofloxacin, or use Medfinder to find a pharmacy with it in stock near you.