When a scratchy throat turns into something nasty, or your child suddenly develops a painful earache, one name occasionally pops up on the prescription — Keftab. Not exactly a household word unless you’ve already tangled with an infection, but in doctor’s offices across the UK and elsewhere, this medicine has been quietly doing its job for decades. It’s not glamorous, but it’s reliable. What’s hiding behind that strange name, and what should you expect if you’re taking it? Spoiler: there’s more to know than the pharmacy leaflet lets on.
Keftab is just the brand name for a medicine called cephalexin, which lives in a family of drugs called cephalosporins. It’s an antibiotic, so its number one mission is fighting off infections caused by bacteria. Not viruses — sorry, your cold or flu will not surrender to Keftab, and taking it “just in case” does more harm than good. It works by messing with the cell walls of bacteria. Imagine the bacteria’s protective shell springing leaks, leaving them exposed and pretty helpless. No wall, no bacteria — your body does the rest.
Keftab has been around since the late 1960s. The folks who first made cephalexin were racing against the rise of penicillin resistance. Keftab became the go-to (especially for people allergic to penicillin) because it’s good at handling common culprits like strep throat, skin infections, stuffy sinus infections, tonsillitis, and what doctors call “uncomplicated urinary tract infections” (which, frankly, are never as simple as that sounds when you have one).
You might hear doctors refer to Keftab as a “first-generation” cephalosporin. What’s that mean? Basically, it’s the oldest branch of the cephalosporin family tree, so it works best on certain “simple” bacteria, not the trickier hospital-dwelling types. So if you’re dealing with a routine infection in the community, Keftab is probably on your doctor’s radar.
This is where things get interesting. Not every bug will drop dead after a dose of Keftab. It’s great against stuff like Streptococcus (think throat and skin infections), Staphylococcus (“staph” infections, including the classic impetigo kids pick up at school), E. coli and Proteus mirabilis (the villains behind many UTIs), and some Klebsiella strains. If you’re allergic to penicillin, or your infection just doesn’t need something strong and fancy, Keftab is an old reliable.
Doctors usually prescribe it in capsule, tablet, or liquid form. Here’s a cool trick — the liquid tastes surprisingly decent for a medicine, so it’s not a battle of wills every mealtime with kids (or some adults). You’ll often see it prescribed twice a day, sometimes four times, depending on what you’re fighting and how bad it is. The course is usually five to fourteen days. Don’t stop early because you feel better; that’s the fastest way to have the germs regrouping before you know it.
Just a heads-up, though: not all infections are Keftab’s territory. Serious pneumonia? Hospital infections? Some sexually transmitted ones? Those need bigger guns. Similarly, if you keep getting the same infection over and over, don’t expect your GP to keep handing out Keftab. They’ll want to see what sneaky bacteria are hanging around and maybe switch tactics.
Keftab is one of those rare medicines that’s both old and still popular, partly because its side effects list, while real, is usually manageable. The main problems most people run into? Nausea, a bit of stomach ache, or maybe loose stools. If you’re unlucky, you might notice yeast infections (thrush) pop up because, while Keftab targets “bad” bacteria, it can upset your normal “good” bacteria too. Unusual taste in the mouth and mild headaches show up for some but rarely stick around.
Allergies are the one big red flag. If you break out in a rash, start itching, or (yikes) start wheezing or notice your face swelling up, drop everything and seek help. It’s rare, but serious reactions — even full-blown anaphylaxis — have happened. According to a 2023 NHS study, less than 1% of Keftab users reported severe allergic reactions, but it’s still not something you want to ignore.
Here’s a pro tip: be honest with your doctor. If you’ve ever had a dodgy reaction to penicillins or other antibiotics, mention it upfront. Cephalosporins and penicillins are chemical cousins, so there’s a slim risk of cross-reaction. Your doctor might pick something else or give you a supervised test dose if you’re really stuck.
Something else to watch for — if you’ve got kidney disease, or are elderly, dosing might need adjusting. The kidneys handle most of the work clearing Keftab from your system. Throw in regular blood checks if you’re on it for ages or you’re juggling a few prescription meds.
There’s more to getting antibiotics right than just picking up the prescription. With Keftab, here are a few tips that can make a real difference:
One cool thing — Keftab isn’t heavily affected by most foods, so you don’t need to time your meals just so. Just stick to the schedule, stay hydrated, and you’re on the right path.
Loads of confusing stories go around about antibiotics like Keftab. Let’s debunk a few:
If you’re prescribed Keftab more than once for the same problem, ask your doctor why and if it’s time for a different approach. Medicine shouldn't be a repeat loop.
Keep in mind the battle against antibiotic resistance started in part because early antibiotics like Keftab were so successful that we overused them. The golden rule: only use them when you genuinely need them, and always as prescribed.
