Immune Protocol
Polymyxin BComplete Dosing & Administration Guide
Cyclic lipopeptide antibiotic from Paenibacillus polymyxa containing 10 amino acids with 6 diaminobutyric acid residues and a fatty acid tail — FDA-approved since 1964 as a last-resort treatment for multidrug-resistant Gram-negative infections including Pseudomonas aeruginosa, Acinetobacter baumannii, and carbapenem-resistant Enterobacteriaceae, targeting lipid A of bacterial lipopolysaccharide with rapid bactericidal membrane disruption
Dose Range
1.5-2.5mg/kg
Frequency
Multiple times daily
Route
Intravenous infusion (primary systemic route)
Cycle Length
4-6 weeks
Dosing
How much
do I take?
Starting Dose
Loading dose 2.0-2.5 mg/kg IV over 1 hour
Polymyxin B dosing begins with a loading dose to rapidly achieve therapeutic concentrations. Administer as IV infusion over 1-2 hours to minimize histamine-related infusion reactions. Calculate dose based on actual body weight (not ideal body weight). Pre-medication with antihistamine may reduce infusion reactions. Obtain baseline renal function (serum creatinine, BUN) before starting. This is an FDA-approved antibiotic — used under physician supervision in hospital settings.
Standard Dose
1.25-1.5 mg/kg IV every 12 hours (maintenance)
Standard maintenance dosing for serious systemic Gram-negative infections. Infuse over 1-2 hours. Monitor renal function (creatinine, BUN, urine output) at least every 48 hours. Target AUC₀₋₂₄ of 50-100 mg·h/L guided by TDM when available. Dose adjust for renal impairment per institutional guidelines. Combine with a second agent (carbapenem, rifampicin, or minocycline) for XDR infections. Duration guided by clinical response and source control.
Advanced Dose
Intrathecal: 5 mg/day; Inhaled: 2.5 mg/kg/day divided q12h; Topical: 10,000-25,000 units/g ointment
Specialized administration routes for specific indications. Intrathecal/intraventricular: 5 mg (50,000 units) daily for MDR Gram-negative meningitis/ventriculitis, preservative-free formulation required. Inhaled/nebulized: adjunct to IV therapy for MDR pneumonia. Topical: component of triple antibiotic ointment (Neosporin) for wound prophylaxis — safe for external use with minimal systemic absorption. All specialized routes require infectious disease specialist guidance.
Timing
Best time to take
Polymyxin B is administered intravenously in a clinical setting. Timing is determined by your healthcare provider based on the treatment protocol and your medical needs.
With food?
IV administration of Polymyxin B is not dependent on meal timing. Your healthcare team will provide specific instructions regarding food and fluid intake around treatment sessions.
If stacking
Polymyxin B should be used as directed by your healthcare provider. If combining with other medications or supplements, discuss potential interactions with your provider. Avoid combining with compounds that have overlapping mechanisms unless specifically guided by a medical professional.
Adjusting Your Dose
Increase if
- +You've tolerated the current dose for the recommended period without significant side effects
- +Therapeutic goals haven't been met at the current dose level
- +Your healthcare provider recommends dose escalation based on your response
- +Lab work or clinical assessments support a higher dose
Decrease if
- -Side effects are bothersome or impacting daily life despite management strategies
- -You experience any signs of an adverse reaction
- -Lab results indicate the need for dose reduction
- -Your healthcare provider recommends a lower dose based on your response
Signs of right dose
- ✓Therapeutic goals being met with minimal side effects
- ✓Stable and consistent response to treatment
- ✓Lab values or clinical markers trending in the right direction
- ✓Good tolerance with manageable or absent side effects
Dosing Calculator
Calculate Your Exact Dose
Step 1: Peptide Weight
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Administration
How do I
use it?
Reconstitution
What you need
- •Polymyxin B vial (lyophilized powder or solution)
- •Bacteriostatic water or sterile sodium chloride for reconstitution
- •Alcohol swabs for cleaning vial tops and injection sites
- •Appropriately sized syringes with fine-gauge needles (27-30 gauge)
- •Sharps disposal container
Injection
Route
Subcutaneous injection (into the fatty tissue just under the skin)—allows for consistent absorption and can be self-administered at home after proper training
Best sites
- •Abdomen (stomach area)—at least 2 inches from the belly button, most popular choice for self-injection
- •Front of thighs—middle to upper portion of the outer leg
- •Back of upper arm—outer area (may need assistance from another person)
Technique
- 1.Wash your hands thoroughly with soap and water before handling supplies
- 2.Clean the injection site with an alcohol swab and let it air dry completely
- 3.Pinch a fold of skin at the chosen injection site
- 4.Insert the needle at a 45-90 degree angle (depending on needle length and body composition)
- 5.Inject the medication slowly and steadily over 5-10 seconds
- 6.Release the skin fold and remove the needle, applying gentle pressure with a clean swab
- 7.Rotate injection sites to prevent tissue irritation or lipodystrophy
- 8.Dispose of the needle safely in a sharps container—never recap or reuse needles
Storage
Signs of degradation
Sample Daily Schedule
Safety
Is it
safe?
Safety Profile
Polymyxin B carries significant nephrotoxicity risk (acute tubular necrosis) and neurotoxicity risk (peripheral neuropathy, neurological effects) requiring strict monitoring. Serum concentrations >5 mg/L associated with increased renal dysfunction; dosing adjusted for creatinine clearance to minimize accumulation. IV or intramuscular use only; intrathecal administration reserved for meningitis with careful dosing. Bacterial resistance monitoring essential as polymyxins remain reserved antibiotics.
Clinical pharmacokinetic studies document polymyxin B mechanism through lipopolysaccharide binding (LPS) neutralization assays. Renal safety monitoring via creatinine clearance and cystatin C shows dose-dependent decline in GFR. Neurotoxicity correlates with serum levels >5 mg/L; electromyography studies show reversible neuromuscular junction effects. Meningitis studies show CSF penetration adequate for bacterial killing despite narrow therapeutic window.
Common Side Effects
Experienced by some users
Nephrotoxicity
Acute kidney injury reported in 34-60% of patients receiving IV polymyxin B. Manifests as rising serum creatinine, decreased urine output, and renal tubular injury. Typically appears within the first week of treatment. Risk increases with higher doses, longer duration, and concurrent nephrotoxic agents.
Management: Monitor renal function (creatinine, BUN, urine output) every 24-48 hours. Ensure adequate hydration. Avoid concurrent nephrotoxins when possible. Dose-adjust or switch agents if creatinine rises >2x baseline. Nephrotoxicity is usually reversible upon discontinuation.
Infusion-related histamine release
Flushing, pruritus, urticaria, chest tightness, and hypotension during IV infusion. Caused by direct polymyxin B-induced mast cell degranulation and histamine release. Dose-rate dependent.
Management: Infuse slowly over 1-2 hours (never IV push). Pre-medicate with diphenhydramine or H1-blocker if prior reaction. Reduce infusion rate if symptoms occur. Usually manageable without discontinuation.
Neurotoxicity
Perioral paresthesias (numbness/tingling around mouth), peripheral paresthesias in extremities, dizziness, and vertigo in 5-15% of patients. Dose-dependent and usually reversible.
Management: Monitor for neurological symptoms daily. Usually mild and self-limiting. Dose reduction may be needed if symptoms are significant. Resolves after treatment completion.
Skin hyperpigmentation
Progressive skin darkening, particularly in sun-exposed areas and head/neck region, with prolonged IV polymyxin B courses. Related to histamine-mediated stimulation of melanogenesis. Reported in 8-15% of patients.
Management: Cosmetic concern — not medically dangerous. Usually reversible over weeks to months after discontinuation. Sun protection may help minimize progression.
Less Common
- •Neuromuscular blockade
These typically resolve with continued use or dose adjustment.
Stop and Seek Help If
- ×Severe or worsening side effects that don't improve with dose adjustment or supportive care
- ×Signs of an allergic reaction—rash, hives, swelling, or difficulty breathing
- ×Your healthcare provider recommends discontinuation based on your clinical response
- ×Development of any new medical condition that may be contraindicated with Polymyxin B
- ×Pregnancy or planning to become pregnant (unless specifically approved for use during pregnancy)
- ×Abnormal lab results or clinical markers that suggest adverse effects
Polymyxin B should only be started, adjusted, or discontinued under medical supervision. This information is for educational purposes only and does not replace professional medical advice. Never stop a prescribed treatment without consulting your healthcare provider first, as abrupt discontinuation may have consequences.
Interactions
With other peptides
- ✓May be used together under medical guidance.
- ✓May be used together under medical guidance.
- ✓May be used together under medical guidance.
With medications
- !Aminoglycosides (gentamicin, tobramycin, amikacin) — additive nephrotoxicity and neurotoxicity; use combination only when absolutely necessary with intensive renal monitoring - Use with caution—discuss with your healthcare provider.
- !Vancomycin at full doses — additive nephrotoxicity; if combination needed, monitor renal function daily - Use with caution—discuss with your healthcare provider.
- !Neuromuscular blocking agents (succinylcholine, vecuronium) — polymyxin B potentiates neuromuscular blockade, risk of prolonged paralysis and respiratory failure - Use with caution—discuss with your healthcare provider.
With supplements
- ✓Multivitamins - Generally safe to take alongside Polymyxin B. Space doses apart if taking oral formulations to ensure optimal absorption.
- ✓Electrolyte supplements - Helpful if experiencing any GI side effects that could lead to dehydration. Safe to combine.
Want the Full Picture?
View the complete Polymyxin B research profile including mechanism of action, clinical studies, effectiveness timeline, and FAQ.
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