Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Cipro Xl. If you are concerned about side effects, discuss the risks and benefits of Cipro Xl with your doctor.

The following side effects have been reported by at least 1% of people taking Cipro Xl. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• dizziness or lightheadedness
• general feeling of being unwell
• headache
• heartburn
• increased skin sensitivity to the sun
• loss of appetite
• mild Diarrhea
• nausea
• nightmares
• restlessness
• ringing in the ears
• stomach discomfort or gas
• sweating
• trouble sleeping
• vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• agitation
• anxiety
• changes in sensation (things taste or smell different)
• coordination problems (unsteady walk)
• fainting
• hallucinations (hearing or seeing things that aren't there)
• hearing changes
• irregular or fast heart rate
• joint pain
• memory loss
• migraine
• muscle pain
• numbness or burning, tingling pain
• pain or swelling in a joint (ruptured tendon)
• severe abdominal or stomach cramps or pain
• signs of Depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
• signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
• symptoms of high blood sugar (e.g., frequent urination, increased thirst, excessive eating, unexplained weight loss, poor wound healing, infections, fruity breath odour)

• symptoms of low blood sugar (e.g., cold sweat, cool pale skin, headache, fast heartbeat, weakness)
• symptoms of worsening Myasthenia Gravis (e.g., muscle weakness, drooping eyelid, vision changes, difficulty chewing and swallowing, trouble breathing)
• symptoms of a vaginal yeast infection (e.g., vaginal itching or burning, thick white odourless vaginal discharge)
• tremor
• vision changes

Stop taking the medication and seek immediate medical attention if any of the following occur:

• confusion or changes in thought patterns
• diarrhea (watery and severe; may also be bloody)
• seizures
• signs of an aortic Aneurysm (abnormal bulge in aorta) or tear in the aorta (e.g., dizziness, loss of consciousness, pulsating sensation in abdomen, sudden severe pain in the chest, abdomen or back)
• signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)
• signs of increased pressure in the brain (e.g., blurred or double vision, Headaches, nausea)
• signs of a severe skin reaction (e.g., blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with Fever or discomfort)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Cipro Xl.

500 mg
Each white-to-slightly-yellow, film-coated, oblong-shaped, extended-release tablet, coded with the word "BAYER" on one side and "C500 QD" on the other, contains ciprofloxacin 500 mg as ciprofloxacin HCl (287.5 mg, calculated as ciprofloxacin on the dried basis) and ciprofloxacin (212.6 mg, calculated on the dried basis). Nonmedicinal ingredients: crospovidone, hypromellose, magnesium stearate, polyethylene glycol, silical colloidal anhydrous, succinic acid, and titanium dioxide.

1000 mg
Each white-to-slightly-yellow, film-coated, oblong-shaped, extended-release tablet, coded with the word "BAYER" on one side and "C1000 QD" on the other, contains ciprofloxacin 1,000 mg as ciprofloxacin HCl (574.9 mg, calculated as ciprofloxacin on the dried basis) and ciprofloxacin (425.2 mg, calculated on the dried basis). Nonmedicinal ingredients: crospovidone, hypromellose, magnesium stearate, polyethylene glycol, silical colloidal anhydrous, succinic acid, and titanium dioxide.

Do not take Cipro Xl if you:

• are allergic to ciprofloxacin or any ingredients of the medication
• are allergic to other medications in the quinolone family (e.g., Norfloxacin, moxifloxacin)
• are also taking a medication called Tizanidine

There may be an interaction between ciprofloxacin extended-release and any of the following:

• acetylsalicylic acid (Asa)
• Amiodarone
• amphetamines (e.g., Dextroamphetamine, Lisdexamfetamine)
• antacids that contain aluminum hydroxide, calcium, and magnesium hydroxide (do not take these products for at least 6 hours before or for 2 hours after ciprofloxacin)
• antipsychotics (e.g., Chlorpromazine, Clozapine, Haloperidol, Olanzapine, Quetiapine, Risperidone)
• BCG vaccine
• Bendamustine
• caffeine
• calcium supplements and multivitamins that contain calcium (do not take these products for at least 6 hours before or for 2 hours after ciprofloxacin)
• Carbamazepine
• Cholera vaccine
• Clomipramine
• inhaled corticosteroids (e.g., budesonide, ciclesonide, fluticasone)
• oral corticosteroids (e.g., dexamethasone, Hydrocortisone, prednisone)
• Cyclosporine
• diabetes medications (e.g., chlorpropamide,  Glyburide, insulin, Metformin, Rosiglitazone)
• didanosine
• Dipyridamole
• Disopyramide
• dofetilide
• Dronedarone
• Duloxetine
• Flecainide
• Flibanserin
• iron supplements (e.g., ferrous fumarate, ferrous gluconate, ferrous sulfate: do not take these products for at least 6 hours before or for 2 hours after ciprofloxacin)
• Lanreotide
• lidocaine
• Lomitapide
• magnesium supplements (e.g., magnesium hydroxide, magnesium oxide)
• melatonin
• Methadone
• Methotrexate
• Methylphenidate
• Metoclopramide
• mifepristone
• multiple vitamins and minerals with Vitamin A, E
• multivitamins that contain iron (do not take these products for at least 6 hours before or for 2 hours after ciprofloxacin)
• mycophenolate
• nonsteroidal anti-inflammatory drugs (NSAIDs; e.g.,  Ibuprofen, Diclofenac, Ketorolac)
• Octreotide
• Oxycodone
• Pasireotide
• pentamidine
• Pentoxifylline
• Phenytoin
• Pirfenidone
• procainamide
• Propranolol
• Quinapril
• quinidine
• quinine
• other quinolone antibiotics (e.g., norfloxacin, Ofloxacin)
• Rasagiline
• Roflumilast
• Romidepsin
• Ropinirole
• sevelamer
• Sildenafil
• sodium picosulfate
• somatostatin
• Sotalol
• Spironolactone
• Sucralfate (do not take these products for at least 6 hours before or for 2 hours after ciprofloxacin)
• sulfamethoxazole
• Teriflunomide
• theophyllines (e.g., Aminophylline, oxtryphylline, Theophylline)
• Thyroid replacements (e.g., desiccated thyroid, Levothyroxine)
• tizanidine
• Tolvaptan
• Tramadol
• Triazolam
• typhoid vaccine
• tyrosine kinase inhibitors (e.g., Bosutinib, Dasatinib, imatinib, Nilotinib, Sunitinib)
• Varenicline
• Warfarin
• zinc
• Zolpidem

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Cipro Xl. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications that you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should take Cipro Xl.

Antibiotic-associated colitis: Cipro Xl, like other antibiotics, may cause a potentially dangerous condition called antibiotic-associated colitis or pseudomembranous colitis. Symptoms include severe, watery diarrhea that may be bloody. If you notice these symptoms, stop taking Cipro Xl and contact your doctor as soon as possible.

Bacterial resistance: Misuse of an antibiotic such as ciprofloxacin may lead to the growth of resistant bacteria that will not be killed by the antibiotic. If this happens, the antibiotic may not work for you in the future. Although you may begin to feel better when you first start taking ciprofloxacin, you need to take all the medication exactly as directed by your doctor to finish ridding your body of the infection and to prevent resistant bacteria from taking hold. Do not take ciprofloxacin or other antibiotics to treat a viral infection such as The Common Cold; antibiotics do not kill viruses, and using them to treat viral infections can lead to the growth of resistant bacteria.

Behaviour and nervous system: Rarely, ciprofloxacin extended-release may affect behaviour and the nervous system. If you experience confusion, tremors, nerve pain, tingling or weakness, depression (including thoughts of harming yourself), hallucinations (hearing, seeing, or feeling things that are not actually there), agitation, anxiety, difficulty sleeping, nightmares, or any other behaviour changes while taking Cipro Xl, contact your doctor.

Blood glucose: Ciprofloxacin, like other medications in this family, may cause changes in blood sugar levels (may cause a loss of blood glucose control) and glucose tolerance may change. People with Diabetes may find it necessary to monitor their blood sugar more frequently while using Cipro Xl.

If you experience symptoms of low blood sugar (e.g., cold sweat, cool pale skin, headache, fast heartbeat, weakness) or symptoms of high blood sugar (e.g., frequent urination, increased thirst, excessive eating, unexplained weight loss, poor wound healing, infections, fruity breath odour), talk to your doctor.

Drowsiness/reduced alertness: Ciprofloxacin may cause dizziness, affecting your ability to drive or operate machinery. Avoid these and other hazardous tasks until you have determined how Cipro Xl affects you.

Hypersensitivity syndrome: A Anaphylaxis (severe allergic reaction) called hypersensitivity syndrome has occurred for some people taking ciprofloxacin. This reaction involves a number of organs in the body and may be fatal if not treated quickly. Stop taking the medication and get immediate medical attention if you have symptoms of a severe allergic reaction, including fever, swollen glands, yellowing of the skin or eyes, or flu-like symptoms with skin rash or blistering.

Kidney function:  Kidney Disease or reduced kidney function may cause Cipro Xl to build up in the body, causing side effects, since ciprofloxacin is removed from the body mostly by the kidneys. If you have reduced kidney function or kidney disease, discuss with your doctor how Cipro Xl may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Cipro Xl, and whether any special monitoring is needed.

Liver function: Ciprofloxacin may reduce liver function and can cause liver failure. If you have liver problems, discuss with your doctor how Cipro Xl may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Cipro Xl, and whether any special monitoring is needed.

If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.

Neuromuscular disorders: Ciprofloxacin may cause increased muscle weakness for people with myasthenia gravis (an autoimmune disorder that causes muscle weakness). If you have myasthenia gravis, discuss with your doctor how Cipro Xl may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Cipro Xl, and whether any special monitoring is needed.

Other infections: Use of ciprofloxacin extended-release for a long time may cause other infections, especially by yeast or fungi. If you notice symptoms of an infection (e.g., vaginal yeast infection symptoms such as thick white discharge and itchiness), contact your doctor.

QT prolongation: Cipro Xl can lengthen heartbeat as shown on an electrocardiogram test, also known as QT prolongation. Very rare cases of abnormal heartbeat have been reported by people taking ciprofloxacin extended-release, but these reports generally involved people who had conditions that predisposed them to abnormal heartbeat, or who had been taking other medications that can increase the risk of developing an abnormal heartbeat.

If you have heart disease and abnormal heart rhythms, or are taking certain medications (e.g., Verapamil, atazanavir), discuss with your doctor how Cipro Xl may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Cipro Xl, and whether any special monitoring is needed. If you develop heart palpitations (fast or irregular heartbeat) or experience fainting spells, stop taking your medication and contact your doctor immediately.

Seizures: Rarely, seizures have been reported with Cipro Xl. If you have a history of Epilepsy or medical conditions that increase the risk of seizures, discuss with your doctor how Cipro Xl may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Cipro Xl, and whether any special monitoring is needed. If you have a seizure while taking Cipro Xl, stop taking it and get immediate medical attention.

Sun sensitivity: Ciprofloxacin extended-release can increase the sensitivity of the skin to sun and increase the chance of Sunburn. Avoid the sun, use sunscreen, and avoid sun beds while taking Cipro Xl. If you must spend time in the sun, use sunblock with minimum SPF 15. Contact your doctor if severe sun sensitivity occurs (e.g., sunburn).

Tendonitis: Ciprofloxacin extended-release may increase the chance of tendon injury. Injury occurs more commonly for seniors who are also taking, or have recently taken, corticosteroid medications (e.g., Prednisone, Dexamethasone), however it can happen to anyone who takes ciprofloxacin. If you experience any new pain in the tendons, stop taking ciprofloxacin extended-release, avoid physical exercise, and contact your doctor.

Pregnancy: Cipro Xl should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking Cipro Xl, contact your doctor immediately.

Breast-feeding: Cipro Xl passes into breast milk. If you are a breast-feeding mother and are taking ciprofloxacin extended-release, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of ciprofloxacin extended-release has not been established for children and adolescents less than 18 years of age.

Seniors: Seniors may require lower doses of Cipro Xl due to age-related decreases in kidney function.