Ciprofloxacin

What Does Ciprofloxacin Do?

Ciprofloxacin is a broad-spectrum antibiotic that treats bacterial infections by inhibiting bacterial DNA replication, commonly used for urinary tract infections, respiratory infections, and skin infections.

How Does Ciprofloxacin Work? (the complicated stuff!)

Ciprofloxacin is a fluoroquinolone antibiotic that operates by inhibiting two critical bacterial enzymes: DNA gyrase and topoisomerase IV. These enzymes are essential for DNA replication and transcription. By disrupting their activity, ciprofloxacin prevents bacteria from synthesising and repairing their DNA, ultimately leading to bacterial cell death. This mechanism makes ciprofloxacin effective against a wide range of bacterial infections, including those in the urinary tract, lungs, and skin, among others.

Drug Type and Category of Ciprofloxacin

Ciprofloxacin is classified as a fluoroquinolone antibiotic. 

What dosage of Ciprofloxacin should you be taking?

According to the British National Formulary (BNF) provided by NICE ¹, ciprofloxacin is available in different formulations, including tablets, oral suspension, and eye and ear drops. The dosage and duration of treatment depend on the specific infection being treated.

For example, for acute pyelonephritis, NICE guidelines recommend a 7-day course of ciprofloxacin. 

What are the side-effects of Ciprofloxacin?

Common Side Effects

• Gastrointestinal:
• Nausea
• Diarrhea
• Vomiting
• Abdominal pain
• Central Nervous System:
• Headache
• Dizziness

Uncommon or Rare Side Effects

• Central Nervous System:
• Insomnia
• Anxiety
• Confusion
• Depression
• Seizures (particularly in those with a predisposition)
• Musculoskeletal:
• Tendon pain, swelling, or rupture (particularly in the Achilles tendon)
• Joint pain
• Skin:
• Rash
• Itching
• Photosensitivity (increased sensitivity to sunlight)
• Cardiovascular:
• Palpitations
• Changes in heart rhythm (e.g., QT prolongation)

Serious Side Effects (Rare but Require Immediate Attention)

• Severe allergic reactions (e.g., anaphylaxis)
• Severe diarrhea, potentially a sign of Clostridioides difficile-associated colitis
• Tendon rupture or damage
• Peripheral neuropathy (numbness, tingling, or weakness)
• Psychiatric effects (e.g., hallucinations, suicidal thoughts)
• Liver toxicity (symptoms include yellowing of the skin or eyes, dark urine)
• Kidney problems (reduced urine output, swelling, or fatigue)

Warnings

• Ciprofloxacin can increase the risk of tendon problems, especially in older adults, those on corticosteroids, or people with organ transplants.

Interactions

Drugs That May Decrease Ciprofloxacin Effectiveness

• Antacids: Containing magnesium, aluminum, or calcium can bind to ciprofloxacin and reduce its absorption. Take ciprofloxacin at least 2 hours before or 4 hours after these medications.
• Calcium or Iron Supplements: Similar to antacids, these can reduce ciprofloxacin absorption.
• Sucralfate: Used for ulcers, it can reduce ciprofloxacin absorption. Avoid taking them simultaneously.

Drugs That Increase Risk of Side Effects

• Corticosteroids (e.g., Prednisone): Increase the risk of tendon rupture.
• Non-Steroidal Anti-Inflammatory Drugs (NSAIDs): May increase the risk of central nervous system effects, including seizures.
• Theophylline: Ciprofloxacin can increase theophylline levels, potentially causing toxicity (e.g., nausea, seizures).
• Warfarin and Other Anticoagulants: Ciprofloxacin may increase the blood-thinning effects of warfarin, raising bleeding risk. Monitoring INR is essential.
• QT-Prolonging Drugs: Ciprofloxacin may increase the risk of arrhythmias when used with other drugs that prolong the QT interval (e.g., amiodarone, sotalol, or certain antipsychotics).

Other Notable Interactions

• Cyclosporine: Ciprofloxacin can increase cyclosporine levels, potentially leading to kidney damage. Monitoring is advised.
• Metformin: May increase the risk of hypoglycemia.
• Phenytoin: Ciprofloxacin can either increase or decrease phenytoin levels, potentially causing seizures or toxicity.
• Methotrexate: Increased risk of methotrexate toxicity when taken with ciprofloxacin.

Food Interactions

• Dairy Products: Milk, yogurt, or fortified juices can bind to ciprofloxacin and reduce absorption. Avoid taking ciprofloxacin with these; take it at least 2 hours before or after consuming dairy.
• Caffeine: Ciprofloxacin can increase caffeine levels, potentially causing jitteriness, insomnia, or palpitations.

Alcohol

• While alcohol does not directly interact with ciprofloxacin, combining them can exacerbate side effects like dizziness, nausea, or gastrointestinal upset. It is advisable to limit alcohol consumption.

Natural Alternatives to Ciprofloxacin

Maintaining a healthy lifestyle

Being generally healthy is a great preventer for bacterial infections. This is down to having a healthy immune system. A healthy immune system has all the defences we need to fight low-level infections. Getting sunlight and vitamin D, eating a balanced diet, drinking plenty of good quality water, and exercise is a great preventer. 

Garlic (Allium sativum)

Garlic contains allicin, a compound with broad-spectrum antibacterial properties effective against Gram-positive and Gram-negative bacteria. Studies suggest it may inhibit the growth of pathogens such as Escherichia coli and Staphylococcus aureus².

Honey (Manuka Honey)

Manuka honey exhibits antimicrobial properties due to its high methylglyoxal content. Research indicates it can effectively combat antibiotic-resistant bacteria, including Pseudomonas aeruginosa³.

Cranberry (Vaccinium macrocarpon)

Cranberry extract is commonly used to prevent urinary tract infections. It contains proanthocyanidins, which inhibit the adhesion of E. coli to the urinary tract lining, reducing infection risk⁴.

Turmeric (Curcuma longa)

Curcumin, the active compound in turmeric, has demonstrated antibacterial and anti-inflammatory properties. It may be effective against pathogens such as Helicobacter pylori and Salmonella⁵.

Oregano Oil

Oregano oil contains carvacrol and thymol, compounds with potent antibacterial activity. Studies have shown its effectiveness against multi-drug resistant bacteria such as Klebsiella pneumoniae and Escherichia coli⁶.

Echinacea (Echinacea purpurea)

Echinacea is known for its immune-boosting and antimicrobial effects. It may help the body combat infections naturally by enhancing immune response⁷.

Green Tea (Camellia sinensis)

Green tea contains catechins, particularly epigallocatechin gallate (EGCG), which exhibit antimicrobial activity against a variety of bacteria, including Streptococcus mutans and Clostridioides difficile⁸.

Probiotics

Probiotics like Lactobacillus and Bifidobacterium strains can help restore gut microbiota balance and prevent infections, particularly in the gastrointestinal tract⁹. It is one of the best things you can do after a dose of antibiotics, but many people recommend probiotics generally. 

Interesting facts about Ciprofloxacin

Ciprofloxacin gained significant attention during the anthrax bioterrorism attacks in 2001. It is approved by the FDA for treating anthrax exposure and is also effective against plague-causing Yersinia pestis.

Ciprofloxacin is associated with an increased risk of tendonitis and tendon rupture, especially in older adults, those on corticosteroids, or individuals with kidney, heart, or lung transplants. The Achilles tendon is most commonly affected.

Due to widespread use, some bacteria have developed resistance to ciprofloxacin. This has prompted cautious prescribing to preserve its effectiveness against serious infections.

Ciprofloxacin is also used in veterinary medicine to treat infections in animals. However, its use in livestock has been criticised due to concerns about antibiotic resistance.

Disclaimer

This article is generated for informational purposes only. It was created in January 2025. Medications and medical guidance can change over time. Therefore, it is essential to consult with your general practitioner or healthcare provider before making any decisions regarding medications or treatment plans. Your GP can provide personalised advice based on your specific health needs and conditions.

References

1. https://bnf.nice.org.uk/drugs/ciprofloxacin
2. Ankri, S., & Mirelman, D. (1999). Antimicrobial properties of allicin from garlic. Microbes and Infection, 1(2), 125-129. doi:10.1016/S1286-4579(99)80003-3
3. Cooper, R. (2008). A review of the evidence for the use of topical antimicrobial agents in wound care: Manuka honey. Journal of Wound Care, 17(6), 241-247. doi:10.12968/jowc.2008.17.6.30114
4. Howell, A. B., & Foxman, B. (2002). Cranberry juice and adhesion of antibiotic-resistant Escherichia coli. Journal of the American Medical Association, 287(23), 3082-3083. doi:10.1001/jama.287.23.3082
5. Jagetia, G. C., & Aggarwal, B. B. (2007). “Spicing up” of the immune system by curcumin. Journal of Clinical Immunology, 27(1), 19-35. doi:10.1007/s10875-006-9066-7
6. Nostro, A., Blanco, A. R., Cannatelli, M. A., et al. (2004). Susceptibility of multidrug-resistant Staphylococcus aureus to oregano essential oil, carvacrol, and thymol. FEMS Microbiology Letters, 230(2), 191-195. doi:10.1016/S0378-1097(03)00890-5
7. Barrett, B. (2003). Medicinal properties of Echinacea: A critical review. Phytomedicine, 10(1), 66-86. doi:10.1078/094471103321648692
8. Friedman, M. (2007). Overview of antibacterial, antitoxin, antiviral, and antifungal activities of tea catechins and related polyphenols. Critical Reviews in Food Science and Nutrition, 47(1), 56-67. doi:10.1080/10408390600677925
9. Ouwehand, A. C., Salminen, S., & Isolauri, E. (2002). Probiotics: An overview of beneficial effects. Antonie van Leeuwenhoek, 82(1-4), 279-289. doi:10.1023/A:1020620607611