What is Penicillin?
Penicillins are a class of antibacterial drugs used in treating diseases caused by a wide range of bacteria.
Penicillins were the first group of antibacterials ever used, and their discovery is said to have changed the course of medicine, saving millions of lives to date.
Penicillin is obtained from the Penicillium fungi, and this drug is given both orally and in an injection.
Today, there are several different types of penicillins, and their primary mechanism of action is killing the bacteria by disrupting their cell walls.
Is Amoxicillin The Same As Penicillin?
Amoxicillin is a semi-synthetic form of penicillin launched in 1972.
While both amoxicillin and penicillin treat bacterial infections, penicillin may be preferred for streptococcal throat infection, bacterial pneumonia, bacterial meningitis, and syphilis.
On the other hand, amoxicillin is more effective against syphilis, dental infections, ear infections, and lung infections like bronchitis.
Can You Get Penicillin Over-the-counter?
Antibiotics like penicillin cannot be purchased over-the-counter without a valid prescription from a certified medical practitioner.
However, some topical antibiotics comprising Neosporin and other generics for application on acne, minor scrapes, and wounds are available as OTC products.
What is Penicillin Used For?
Natural penicillins and their synthetic derivatives are the most widely used antibacterials globally.
Penicillins are effective against the following types of bacteria:
- Streptococci
- Listeria
- Neisseria gonorrhea
- Clostridium
- Peptococcus
- Peptostreptococcus
- H.influenzae
- E.coli
- Salmonella
- Shigella
- Pseudomonas aeruginosa
Penicillin-based antibiotics are commonly used to treat infections like
- Otitis media (ear infection)
- Abdominal infections
- Sinusitis
- Pharyngitis
- Typhoid
- Urinary Tract Infections (UTI)
- As a prophylactic antibiotic cover in high-risk patients before surgery
- Bone infections (osteomyelitis)
- Bacterial infection of the kidneys
This class of drugs is also used to treat some serious conditions such as
- Pneumonia
- Meningitis
- Endocarditis
- Blood infections (sepsis)
- Uncomplicated gonorrhea
Can Penicillin Be Used For Treating STDs?
Penicillins, along with B-lactam antibiotics, are the first line of treatment for sexually transmitted diseases (STDs).
Penicillins are effective in treating all stages of syphilis and gonorrhea.
Is Penicillin a Pain Killer?
Penicillin is an antibiotic that treats bacterial infections and diseases. It works to kill bacteria and does not cause pain relief.
How Does Penicillin Work?
Penicillin and other drugs in its class work by preventing bacterial cell wall synthesis by attacking peptidoglycans.
Peptidogylancs are a mesh-like structure and an integral part of the bacterial cell wall.
The cell wall protects bacteria from the environment and prevents external fluids and other particles from entering the cell.
The lack of a cell wall results in surrounding fluids gushing into the bacterial cell, leading to the bursting of the cell and eventual death.
Side Effects of Penicillin
Like most drugs, penicillin may cause side effects in some individuals.
Commonly encountered side effects of penicillin are:
- Nausea
- Vomiting
- Stomach pain
- Headache
- Heartburn
- Confusion
- Skin rash
A few rare side effects that may occur on taking penicillin include:
- Seizures
- Oral fungal infections
- Shortness of breath
- Fainting
- Low platelet counts and unusual bleeding
- Anaphylaxis (a severe allergic reaction)
Does Penicillin Make You Feel Sleepy?
When the antibiotic is working to fight the infection, it can make you tired and fatigued.
Penicillin: Interactions With Other Drugs
If your doctor has prescribed penicillin to treat your bacterial infection, inform them about the drugs and supplements you are currently taking.
Some penicillin-drug interactions
- Other members of the penicillin family: Since members of the penicillin family work in the same way and have the same structure, you must avoid taking more than one drug from the family.
- Cephalosporins: Cephalosporins and penicillins have the same beta-lactam ring. It is recommended to take either of the drugs and never both.
- Methotrexate: When penicillin is taken with methotrexate, it may increase the blood level of methotrexate to dangerously high levels, resulting in symptoms like nausea, vomiting, ulcers in the mouth, and low blood counts.
- Doxycycline: Combining doxycycline with penicillin may reduce the effect of the latter, affecting its efficacy in treating the bacterial disease.
Can You Be Allergic To Penicillin?
An allergy to penicillin is an abnormal reaction of your immune system to the drug.
Around 10% of people, less than 1% of people are dangerously allergic to the drug.
Common signs and symptoms of penicillin allergy are
- Skin rash
- Hives
- Itching
- Fever
- Shortness of breath with or without wheezing
- Itchy, watery, runny eyes
- Swelling
Some delayed signs of a penicillin allergy that occur after a few days or weeks of exposure to the drug are:
- Serum sickness
- Inflammation of the kidneys
- Drug-induced anemia
- Steven Johnson Syndrome
People allergic to penicillins are usually allergic to other antibiotics having a beta-lactam ring.
In these individuals, broad-spectrum antibiotics are preferred, but they may cause more severe side effects.
For this reason, your doctor may confirm your penicillin allergy with tests and determine the best possible antibiotic depending on your test results.
Genetics of Penicillin Allergy
The human Leucocyte Antigen (HLA) system is a complex set of genes present on chromosome 6.
These genes are associated with allergic reactions, including penicillin allergy.
rs114892859
rs114892859 is a single nucleotide polymorphism (SNP) in the HLA-B gene.
Tagged as HLA-B*55:01, people of European ancestry with the T allele of rs114892859 SNP are at a greater risk of developing penicillin allergy.
rs7192
rs7192 is an SNP in the HLA-DRA gene on chromosome 6 and has been associated with food allergies and allergy to penicillin and amoxicillin.
People with the G allele of this SNP had a lower risk of developing penicillin allergy than those with the T allele.
rs11740584
This SNP has been associated with penicillin and amoxicillin allergies.
Individuals with the G allele of SNP rs11740584 have a greater risk for penicillin allergy than those with the T allele.
Analyze Your Genetic Response to Penicillin
Recommendations For Safe Usage of Penicillin
Take On An Empty Stomach
The best way to take penicillin tablets is with a glass of water, preferably on an empty stomach, unless directed by your physician.
Avoid Acidic Beverages
Avoid consuming acidic juices or other beverages within one hour of taking penicillin, as it may prevent the drug from acting effectively.
Take The Prescribed Dosage
Always take penicillin in the dosage prescribed by your doctor for the required number of days.
If you miss a dose, do not compensate for the same by taking an extra dose later on in the day.
Inform Your Doctor About Other Medications
Before taking penicillin or its derivatives, inform your doctor about other medications and supplements that you are currently taking to avoid interactions and adverse effects.
Inform your doctor if you are on a low-sodium diet, as some penicillin derivatives may require adequate sodium for their effect.
Mention Any History Of Side Effects
If you have a history of side effects of penicillin or any other beta-lactam ring-containing antibiotic, inform your doctor about the same.
Summary
- Penicillins are the earliest discovered class of antibiotics used in treating bacterial infections.
- Penicillins act by interfering in the bacterial cell wall formation process.
- Penicillins are prescription drugs and cannot be obtained over the counter at drug stores.
- Penicillins, both natural and semi-synthetic, are effective against a wide range of bacteria like Streptococci, Neisseria gonorrhea, Salmonella, etc.
- Though considered a safe drug, penicillins may cause side effects like nausea, vomiting, stomach pain, headache, and skin rash.
- Inform your doctor about your medical history and current medications to avoid adverse drug interactions.
- Some SNPs in the HLA gene have been associated with an increased risk for penicillin allergy.
- Follow your doctor’s instructions and prescription while taking penicillin.
References
- https://www.webmd.com/a-to-z-guides/whats-the-difference-between-penicillin-and-amoxicillin
- https://www.drugs.com/medical-answers/can-buy-antibiotics-over-counter-3121697/
- https://www.rxlist.com/how_do_natural_penicillins_work/drug-class.htm
- https://www.medicinenet.com/penicillins-injection/article.htm#what_are_examples_of_penicillin_antibiotics_available_in_the_us
- https://www.cdc.gov/std/treatment-guidelines/penicillin-allergy.htm
- https://www.medicalnewstoday.com/articles/216798#quick_facts
- https://www.mayoclinic.org/diseases-conditions/penicillin-allergy/symptoms-causes/syc-20376222
- https://www.ncbi.nlm.nih.gov/snp/rs114892859
- https://www.snpedia.com/index.php/Rs7192
- https://pubmed.ncbi.nlm.nih.gov/18538381/
A Sneak Peek Into The Gene Allergy Report
Get Insights On Common Allergies From Your 23andMe, AncestryDNA Raw Data!
