Keflex (cephalexin) is a very commonly used brand-name antibiotic and member of the first-generation cephalosporin antibiotic class. Cephalexin is frequently used to treat bacterial infections, such as respiratory, skin, and urinary tract infections. Its efficacy and broad-spectrum activity make it a popular option, but its widespread use necessitates understanding its side-effects and risks.
Keep in mind as you read this that it is manufactured in China.
My husband had to have prostate surgery this year and was prescribed oral Keflex pre- and post-op. It made him extremely sick both times, and on the third day of the second round, he had what appeared to be a stroke, although it was not. He blacked out, had seizure tremors and vomited as his eyes rolled back in his head right in front of me. He came to minutes later, but he remained groggy and unstable for days and had periods of bradycardia which we needed to monitor, prolonging his hospital stay.
In talking with neighbors about our experience at a cookout recently, one woman related that her Mom took Keflex for a uti and got hives all over her body, along with swelling of her face and difficulty breathing. She had to be rushed to the emergency room. She also developed neuropathy of her feet.
Still, most people are not aware of these serious side-effects until they have them.
Afterwards, I did a deep dive on Keflex, and this is what I found on this common, seemingly innocuous antibiotic.
Mild side-effects of Keflex include:
Mild side effects have been reported with cephalexin (source). These include:
Serious side-effects and reactions of Keflex
• Cephalosporins like Keflex can cause anaphylaxis which can manifest with swelling, hives, trouble breathing, abdominal pain, and dizziness from low blood pressure. This life-threatening reaction requires immediate emergency medical services, including the injection of epinephrine.
Immune reactions to Keflex can extend beyond common allergic reactions. The drug treatment can trigger the immune system to attack different body systems, including the kidney (interstitial nephritis), blood cells (hemolytic anemia), joints (serum sickness), and skin (SJS and TEN). Symptoms of Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) include skin rash with skin blistering and acute necrosis, along with ulcers on the eyes, mouth, and genitalia. These severe skin reactions are rare, but are potentially fatal. (source)
• Keflex, not uncommonly, can fire up a C. difficile infection (C.Diff) in the large intestine that can quickly progress to a life-threatening medical condition. C.Diff colitis is different from routine antibiotic-associated diarrhea include watery stools, mucus in stools, fever, and stomach pain.
• Hemolytic anemia, the destruction of circulating red blood cells, and aplastic anemia, the lack of bone marrow production of red blood cells. (source)
• Immune thrombocytopenia, a condition characterized by low platelet counts and can lead to purpura (bruising). (source)
• Prolonged prothrombin time (source)
• Neurotoxicity (source)
• Seizure (source)
• Interstitial nephritis (kidney disease, swelling, and dysfunction from inflammation)
• Cholestatic jaundice (jaundice from lack of bile flow) affecting the liver
Call your doctor right away if you experience any of the following symptoms (29):
- Rash
- Itching
- Swelling of the face, tongue, or throat
- Trouble breathing
- Dizziness
- Severe, watery diarrhea
- Fever
- Increased bleeding and bruising
- Altered mental state or level of consciousness
- Seizures
Tendon disorders include Achilles Tendonitis and tendon rupture:
Study: Cephalexin-associated Achilles Tendonitis: Case Reports of Drug-induced Tendinopathy
Another study: “Do antibiotics cause mitochondrial and immune cell dysfunction?” This study answers with a clear ‘Yes!’ “
“Antibiotics can affect immune and bioenergetic function and this can potentially compromise the host’s ability to both counter infection and maintain organ functionality. Other adverse consequences are… effects on the efficacy of anti-cancer medications,2 organ–organ crosstalk1 and the Herxheimer reaction, in which release of pathogen constituents such as endotoxin and DNA activate proinflammatory pathways.” (source)
“From Healthy to Barely Functioning After Taking Bactrim and Keflex” is frightening to read.
Side-effects of Keflex in older patients
The kidneys primarily excrete cephalexin, so in seniors, the increased prevalence of kidney disease or renal impairment, as well as a longer list of conflicting medications, may necessitate an adjustment to the antibiotic or dosing plan. (source)
Doctors may not check to see if a patient has kidney problems before giving a Keflex prescription, so I advise getting a Complete Metabolic Panel (CMP) yearly in your blood work to keep track of your GFR, or Glomerular Filtration Rate. (Your kidney function is still considered normal if the GFR number is 90 or greater. If your GFR is 45, you know that your kidneys are working at approximately 45 percent of the normal rate.)
How long do Keflex side-effects last?
The duration of Keflex side-effects can be quite variable. Nausea, mild diarrhea, and fatigue may last only as long as the antibiotic course, however, immune-mediated reactions can be longer. Allergic reactions can continue to produce symptoms for days to weeks. Anaphylaxis may require acute management for hours to days. SJS or TEN could require critical care treatment for weeks.
C.Diff colitis may gradually worsen while on Keflex or may not even arise until weeks after completion of the medication. Special antibiotic treatment may be needed for C.Diff colitis to resolve. (source)
Hopefully, this information will prevent those of you reading here from injury you never intended. Look for a naturopathic doctor you can really talk with and who will recommend natural remedies first.
And remember, antibiotics DO NOT work for viruses. Using an antibiotic for a virus, like a cold or the flu:
• will not cure the virus and likely undermine your immune system even more
• won’t help you feel better
It used to be best practice to get a culture before taking an antibiotic, but that recommendation has been removed… Hmm, I wonder why? As usual, follow the money!
Alternatives to an antibiotic
Since I am allergic to all antibiotics and need to rely on natural remedies that SUPPORT the immune system and gut microbiome rather than CRUSH it, I have written extensively on the ways that work for me and my family. You should know about these BEFORE you need them, so READ these posts to the end and maybe twice to really gain understanding.
Here are just a few of the solid alternatives that have been effective for us over the years:
First off, for UTI’s now I ALWAYS recommend homeopathic cantharis 200c. Read #2 in this post: Homeopathy For My Family: Colic, UTIs, Grief & More
Using Essential Oils As Alternative To Antibiotics: My Recipe & Tips (for 20 years this was my go-to for my kids)
Dr. Mercola: Nebulized Peroxide, the Single Most Effective Early Strategy (this simple protocol saved the life of SO many during Covid and kept them OUT of the hospital)
4 Nebulizer Treatments We Can Do at Home to Stay Out of the Hospital (this post will jump start your research)
Nature’s Penicillin: For Pneumonia, Earache, Bronchitis & More (this is super easy to make and very effective)
DIY Liposomal Vit C: Way Cheaper than Store-Bought & More Absorbable (liposomal C is very powerful and you can save $$ making your own)
DIY Natural Antibiotic Recipe using Turmeric and Medicinal Manuka Honey (this just makes everything better)
Chiropractic Found Better Than Drugs for Children’s Ear Infections (especially helpful for children so you can say NO to antibiotics)
Grapefruit Seed Extract: Broad-Spectrum Anti-Microbial For MRSA, UTI & Candida (GSE is both antiviral and antibacterial)
Penicillin Soup: AKA Healing, Medicinal Chicken Noodle Soup (eat this alongside any of these remedies to strengthen your immune system)
Free Antibiotic that Grows in the Woods for UTIs, Lung Infections, Strep (and you can buy this already prepared to have on hand)
”If people let the government decide what foods they eat and what medicines they take, their bodies will soon be in as sorry a state as are the souls who live under tyranny.” ~Thomas Jefferson
***For the Full Spike Protein Protocol to protect from transmission from the “V” and to help those who took the “V”, go here.
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S.H.
Of course. Today I was prescribed Keflex for an infected cyst I had to get lanced and drained. Now I read this literally the same day I began taking it. 500 mg, and I have taken two so far. I haven’t experienced anything crazy, but do have weird hot flashes but no fever. Should I get it replaced with Doxycycline?
Jacqueline
Hi, S.H.,
Not everyone experiences the side effects, thankfully. I am praying you don’t have any more hot flashes or other side-effects at all.
But no, I would not switch midstream. It may just complicate things and add to the side-effects. Stay hydrated, get extra sleep, worship and praise the Lord who created you for healing, etc.
Sending peace,
Jacque
PS S.H. If you saw Danae’s comment about castor oil, I second that. Castor oil is a great way to “pull” cysts and also, there is a “Drawing” homeopathic that rids the body of anything that needs to be drawn out of the body. You can find it at narayaniremedies.com here: https://narayaniremedies.com/pillules/739-5444-drawing.html#/1-size_gm-7gm/14-potency-6x The longer write on this product states, “any morbid matter to be pulled out of the body will react to drawing pillules – be it mucous in the sinus, tonsils, ears, uterus or rectum, and it works in bringing to maturity boils, carbuncles” and draining them. And i understand this would also bring to a head cysts, fluid filled or pus filled. I have this remedy and have used it for splinters and thorns with true results. ~J
Danae
With cysts – especially in the breast aerea or under the armpit I would put poultices with castor oil on… I had two cysts (I got right after having to eat “fried food” at a party “out of politeness”). It took 3-4 days of clean eating and castor oil to get rid of them. As Jacque says as well in her posts – clinopolith or Advanced TRS will always support the body when healing as most problems are connected to toxicity. Wishing you love and healing.
Jacqueline
Danae, I agree – castor oil is a great way to “pull” cysts and there is a “Drawing” homeopathic that rids the body of anything that needs to be drawn out of the body. You can find it at narayaniremedies.com here: https://narayaniremedies.com/pillules/739-5444-drawing.html#/1-size_gm-7gm/14-potency-6x The longer write on this product states, “any morbid matter to be pulled out of the body will react to drawing pillules – be it mucous in the sinus, tonsils, ears, uterus or rectum, and it works in bringing to maturity boils, carbuncles” and draining them. And i understand this would also bring to a head cysts, fluid filled or pus filled. I have this remedy and have used it for splinters and thorns with true results. TRS also has a way of drawing and bringing to a head if close to the surface, if used topically repeatedly for several days, but that, of course, is not its greatest strength which is to remove toxins and metals through the kidneys and stool when taken orally.
And thank you for your very kind remarks. You are a blessing like the blessing mentioned in Pierre Pradervand’s book! Thank you for reaching out in this way… powerful love conveyed through genuine kindness!
Blessings back to you, friend!
Jacque
Danae
Brilliant. Thank you for the information. Have contacted them to see if they deliver the remedy to Europe. This is definitely something to have at hand.
By the way, can I ask you if you have an idea what might be supportive for coughing in the morning? I tried a lot to help my better half and it got better. There is a stress component to the coughing. Changing to warm breakfast (no yogurt milk causing mucus) was a game changer, but there is still coughing going on. Astragalus helps, so does NAC. Just if something comes to mind. Thank you.
Jacqueline
Danae, mullein may be helpful for your husband: https://deeprootsathome.com/preparedness-herb-mullein/
Also you might try this which never fails to stop a prolonged cough: https://deeprootsathome.com/no-side-effect-cough-remedy-homemade/
You might increase his intake of Vitamin C per day. Vit C is so strengthening on many fronts (try to get up to at least 4,000 mg/day in divided doses). This post gives guidelines for recommended ranges of vitamins: https://deeprootsathome.com/child-teen-dosages-9-key-nutrients-to-prime-their-immune-systems/
Fire Cider is a homemade way to increase vit C and build the immune system: https://deeprootsathome.com/fire-cider-popular-folk-remedy-for-digestion-colds-chills-coughs/
There are many natural options.
I hope that helps, ~J
Danae
Thank you Jacque for taking time to answer all of us. We tried Mullein Tea for 1 month in March, but it had no effect on his condition (part is stress…). Unfortunately, any vinegar smell (bit of a pitty as the remedy sounds really good) drives my better half to run out of the room. So I have to work with what he can accept and do without major resistance. I am giving him 2000 mg of Vitamin C in the morning since the plandemic. And that helped with so many things – he has definitely less headaches. But will increase to 4000 mg and see if that might just give boost. Wishing you and your family an inspired and wonderful time.
Jacqueline
Danae, I failed to mentioned the Narayani formula for stress and anxiety: https://narayaniremedies.com/pillules/636-tension.html
We take this on the busiest, most stressful weeks. I do hope they can ship to you!
I am praying for your dear husband now. He is blessed to have you! ~Jacque
Danae
Thank you, Jacque,much appreciated. Will definitely check out the stress formula too… Have a wonderful day.
gena taylor
I have had SJS three times while I was in the Army, due to an allergy to phenobarbital, which I was not even aware was in the asthma medicine I was prescribed. Each time I had the reaction, which seemed to be the next morning after having taken one of the Tedral pills, I would get up, go into the bathroom and notice in the mirror that I had skin inside my mouth peeling off, leaving my mouth very raw and sore. I went to the dental clinic who gaped and even took photos but had no idea what was going on. Then the vaginal area swelled so much the skin split. I went to the gyn clinic, who also had no idea what was going on. And then I started getting sores in my eye lids, and the eye clinic also had no idea what was going on. Each time the reaction lasted over a week, during which time I was told to eat a liquid bland diet in the mess hall, which consisted of whichever meal it was, with no seasoning, liquified, usually into a very unappetizing brown liquid, which I never could make myself consume. I was given liquid Xylocaine, which would gag a maggot, for the constant pain in my mouth.
After the third time that happened, I went to the Internal Medicine office, which was where the Tedral had been prescribed, and mentioned to them that the reaction seemed to always occur the next morning after I had taken one of the pills they had given me. The doctor had immediately said it was SJS, and that I must be allergic to barbiturate’s. He offered to admit me to the hospital, but I declined, since I had done OK by that time without hospitalization. I had lived on vanilla milkshakes, which I would buy in town since there was no way in hell I was going to drink that brown, nasty soup they were making for me at the messhall.
The last time I had had the SJS was after a back surgery after getting out of the Army, where the doctor had prescribed a narcotic pain medicine that I am apparently allergic to. I think they almost killed me that time, since they gave me the shots almost as soon as I came to from the previous shot. My mouth had been completely raw and I could not eat a thing. They thought I wasn’t able to eat due to pain from the back surgery and never gave me time to tell them I thought there was a problem with the pain medicine. I think that medicine was Delaudid (sp?). I avoid narcotics, and most medicines that I am unfamiliar with. I have taken Keflex, and although I didn’t have the more severe reactions you list, I got so sick within a day or two of starting it, that I quit taking the medicine, although the doctors usually told me to keep taking it.
Jacqueline
Gena, remember I said you should write a book? It is a wonder that you are still alive and making a difference in this world after all you’ve been through!
Sending love to you, my friend!
Jacque
gena taylor
((Jackie))
Danae
Ohhh! Thank you for letting us know. Hope your husband is better. So good that you share this.. all this type of “pharma poisoning” is far more common than people think. Blessings & healing. Every of your posts is waking someone up!
Jacqueline
Aw, thank you, Danae. You encourage me to keep on writing.
And, yes, he is doing SO much better since that rough experience. After I saw what was happening and researched if Keflex could make him so sick, we got all the poison out asap. I had him drink a couple bottles of TRS right after surgery bc they gave him 2 more IV antibiotics during surgery and the next day, too. (He drank 2 whole bottles TRS in 4 days and then a couple more spread out over 2-3 weeks). We are in the process of restoring his gut now and it’s almost back to normal. Thank you for asking! God answered our prayers for protection.
We are very thankful! ~Jacque
PS, I don’t know if you saw this post, but I am very thankful for this product. Pls read to the end: https://deeprootsathome.com/why-zeolite-is-so-good-for-cleaning-up-the-body/
Danae
Your posts are amazing. And yes, I have tried Advanced TRS during the plandemic and read all your posts. In my case, I did not feel any “detox” symptoms with Advanced TRS as I have been detoxing for 18 years to get my health back. As I am now eating very much according to TCM I get stronger each year. I have Advanded TRS in my healing cabinet with something I got from Switzerland AION A a clinopolith earth from a very special place that has healed a lot of people. But Advanced TRS is great for travelling as well. I have learned so much over the years from you. I am so glad to hear your husband is better…sounds as if he had to go through an extreme time. Again God, love and a bit nature are the best healers. I had to laugh last year, my husband wanted to know our blood groups and we both went to get our blood taken and got our blood work done as well..(I have not been to an MD for 18 years!). The MD asked what medication are you taking and he said nothing – but occasionally a headache tablet. She asked nothing? Not even statins, or blood pressure? He said no? She shook her head and asked again. He said, smilingly nodding at me – she is my MD!!! I need nothing else. This is when women empower themselves with natural healing and prayer… I am passionate that women take back there healing power in families! It changes everything. I love a book that changed my life when I prayed for months that I need something to help me during the day to stay aligned and positive. I pick up energies so quickly. I found the book “The gentle art of blessing” by Pierre Pradervand. To understand that we can bless rather than react has caused so many small miracles in my life… and now I love going out… when something disrupts the day… like someone being angry or negative. I bless them silently… it keeps me in balance and often changes the situation.. in subtle or even amazing ways… Anyhow, I digress. Sending you love and thanks.
Cara Black
I never go to the DR. I have to be half dead or have an emergency, LOL. But, alas, I went to the urgent care yesterday anyway for what appeared to be a UTI; I was afraid it would turn into kidney infection. Dr. told me there was “a little infection” in my urine. (Really wasn’t helpful, didn’t get a real diagnosis) We chatted a little about supplements, and just thought I was a nut for living naturally. It’s amazing how it feels like I’m in a jail cell in one of those rooms! I mean it: it’s scary and they make you feel crazy for believing in natural living, herbs and homeopathy. I felt like they were gonna come in with a straight jacket when I told them I don’t do vaccines, mammogram, pap smear. I didn’t tell her I had been taking colloidal silver for the past five days. She prescribed Cipro for UTI. I have not taken any kind of prescription for YEARS, and when I read the four-page insert describing all the side effects, I was floored! It’s amazing to me that these meds are cleared for use and that folks just take them because the Dr. says so. I think I’d rather be sick than to take this stuff and be worse off! Thanks, Jacqueline. You’ve taught me so much over the years, and I love using what the Lord has given us for healing.
Jacqueline
Oh, Cara, please do not take the Cipro. It is so horrible and can lead to life-long debility or even death. It IS like a chemo drug and disrupts the mitochondria as I outline in this post:
https://deeprootsathome.com/your-dna-floxed-by-cipro-levaquin-they-act-like-chemo-drugs/
And here are 2 posts that clearly show the dangers to large numbers (not all, of course) of people who take the fluoroquinolones like Cipro, Levaquin, and others of that class of drugs.
https://deeprootsathome.com/fluoroquinolone-antibiotics-cipro/ and https://deeprootsathome.com/serious-fda-alerts-fluoroquinolones-2018/
There is a solid alternative in cantharis 200c for a simple uti. It has worked well for many of those who I’ve recommended it to. I wrote about this here in the #2 story: https://deeprootsathome.com/homeopathy-for-my-family-colic-bladder-infection-grief-more/
You can also add D-mannose, uva ursi and usnea lichen into your regimen. All of them are significantly helpful. I write about them down in this post: https://deeprootsathome.com/antibiotic-that-grows-in-the-woods-utis-lung-infections-strep/
I just updated it today for context since I haven’t had another uti again since then.. not sure that it is even related, but so interesting to me since I used to get them all the time!
I hope that helps some.
Blessings and peace,
Jacque
Danae
I agree 1000% with Jacque… chemicals wipe out the entire live giving microbiome… I just ordered Uva Ursa!!! My knight on my side had lung problems… and we stopped the soar throat with silver-copper tincture (https://de.iherb.com/pr/sovereign-silver-bio-active-copper-hydrosol-10-ppm-4-fl-oz-118-ml/113708) … however, the lung problem breathing persisted until I got him a probiotic that is recommended to be taken with antibiotics…within ours he recovered after 2 weeks of persistent cough… It is sometimes divine intervention, intuition to find what works… but with chemical drugs it is Russian roulette… with nature if it does not work, it does no harm… Thanks, Jacque, as always! And hope Cara that you recover soon and have a wonderful healthy and happy time.