Ciprofloxacin is not one of the antibiotics you're told to avoid alcohol with — the NHS says you can drink with it — but because the drug itself can affect your nervous system and make you tired or dizzy, keeping alcohol light (and skipping it if the medicine is affecting your head) is the sensible move.
Ciprofloxacin is a fluoroquinolone antibiotic, and the UK's NHS is direct that alcohol is allowed with it: "Yes, you can drink alcohol with ciprofloxacin." So this is not like metronidazole, where you're warned off alcohol entirely. The reason to still be careful is overlapping side effects, not a stated chemical clash. The NHS notes ciprofloxacin "may make you feel tired or less alert," and MedlinePlus (U.S. National Library of Medicine) warns that "taking ciprofloxacin may affect your brain or nervous system and cause serious side effects. This can occur after the first dose" — its listed symptoms include dizziness, lightheadedness, and difficulty falling asleep or staying asleep. Alcohol independently causes dizziness, drowsiness, and disturbed sleep, so drinking heavily can worsen these effects or make them harder to tell apart. A small amount is permitted per the NHS; getting drunk while your nervous system may already be irritated by the drug is the part to avoid.
See how the medicine affects you before adding any alcohol: if ciprofloxacin is already making you tired, dizzy, or unable to sleep, hold off — the NHS gives this same "know how you react before you drive or ride a bike" advice. Take seriously and call your doctor about warning signs that are from the drug, not the drink, and that MedlinePlus says can begin even after the first dose: tendon pain, swelling, or a snap/pop (e.g., back of the ankle); numbness, tingling, burning, or weakness in the arms or legs; and seizures, tremors, hallucinations, severe confusion, or new anxiety, depression, or thoughts of self-harm. Be most cautious with alcohol if you're older, prone to dizziness or falls, or have a seizure or mood disorder. One real timing rule people mix up with alcohol is actually about dairy/added-calcium drinks — the NHS says leave a gap of at least 2 hours between ciprofloxacin and those, because they block its absorption; there is no stated separation window for alcohol. Call a pharmacist or doctor if you feel markedly dizzy, confused, or unwell, if any tendon/nerve/mood signs appear, or if you're unsure given your other medicines or conditions.
This is general reference, not medical advice, and not a guarantee of safety. Interactions depend on your doses, health conditions, and other medicines. Always confirm with your pharmacist or doctor before combining products, and follow the dosing on each label.