Get emergency medical help if you have signs of an allergic reaction to Keflex (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning eyes, skin pain, red or purple skin rash with blistering and peeling).
How long does it take for an allergic reaction to cephalexin?
Studies show that more than 90% of the drug passes through the urine within eight hours of a single, isolated dose of Keflex. Peak urine concentrations following a 250-mg dose were 1,000 mcg/mL. When a full antibiotic round of cephalexin is completed, it can take up to 72 hours for the patient to eliminate the drug.
What are the side effects of cephalexin 500mg?
Cephalexin may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- stomach pain.
- rectal or genital itching.
- extreme tiredness.
Can you take Keflex if you have an allergy to penicillin?
Kids or adults who are allergic to penicillin may be able to take one of these antibiotics instead: Azithromycin (Zithromax, Zmax, Z-Pak) Cephalosporins, including cefixime (Suprax), cefuroxime (Ceftin), and cephalexin (Keflex) Clarithromycin (Biaxin)
How long does it take for Keflex to get in your system?
A: Following an oral cephalexin dose, 90% of it will be out of your system within eight hours. The body gets rid of cephalexin by excreting it in the urine. This process can take longer in people with decreased kidney function.
Is 500mg of Keflex 4 times a day too much?
The dose of cefalexin can vary but for most infections you will take 500mg, two or three times a day. The dose may be higher for severe infections and lower for children. Try to space the doses evenly throughout the day.
Is Cephalexin 500 mg a strong antibiotic?
Cephalexin is a first-generation, cephalosporin antibiotic. It belongs to a bigger classification of antibiotics known as beta-lactam antibiotics. It is generally effective against bacteria involved in upper and lower respiratory tract infections, otitis media, mastitis, and skin, bone, and joint infections.
What foods should I avoid while taking cephalexin?
Acidic foods such as citrus juice, carbonated beverages, chocolate, antacids and tomato-based products such as ketchup can all interfere with drug absorption. Have your child avoid these several hours before and after taking the medication, said Seidman. With the exception of yogurt, avoid dairy, said Kohlstadt.
Is cephalexin hard on the kidneys?
For people with kidney problems: If you have kidney problems or a history of kidney disease, you may not be able to clear this drug from your body. This may increase the levels of this drug in your body and cause more side effects. Your doctor may adjust your dose if you have kidney disease.
What STD does cephalexin treat?
The use of cephalexin in the treatment of gonorrhea.
What antibiotics should you avoid if you are allergic to penicillin?
It is generally recommended that you avoid all drugs in the immediate penicillin family (amoxicillin, ampicillin, amoxicillin-clavulanate, dicloxacillin, nafcillin, piperacillin-tazobactam as well as certain drugs in the cephalosporin class (a closely related class to penicillins).
What are the allergic reactions to penicillin?
Common allergic reactions to penicillin include rashes, hives, itchy eyes, and swollen lips, tongue, or face. In rare cases, an allergy to penicillin can cause an anaphylactic reaction, which can be deadly. This type of reaction usually happens within an hour after you take penicillin.
How long does an allergic reaction to penicillin last?
How long does an allergic reaction to penicillin last? Everyone’s body chemistry is different and the allergic reaction to penicillin will vary from person to person. However, even with treatment, the signs and symptoms of an allergic reaction to penicillin can last anywhere from 2 to 4 weeks.
What is Keflex 500mg used to treat?
Keflex (cephalexin) is a cephalosporin (SEF a low spor in) antibiotic. It works by fighting bacteria in your body. Keflex is used to treat infections caused by bacteria, including upper respiratory infections, ear infections, skin infections, urinary tract infections, and bone infections.
How long does it take for antibiotics to leave my system?
It usually takes around 5.5 x elimination half-life (hours) before a drug is completely cleared from your system. So if we take the maximum elimination half life of 22 hours, it would take 121 hours (5.5 x 22 hours) approximately 5 days before the medicine is eliminated from your system.
How do I take Keflex 4 times a day?
Four times each day: this should be once in the morning, at around midday, once in the early afternoon and once in the evening. Ideally, these times are about 4 hours apart, for example 8 am, midday, 4 pm and 8 pm.