Can I order colistin online in Canada?

No. Colistin is a prescription-only medication available only through licensed hospitals and cannot be legally purchased online or without a physician's prescription. Any website claiming to sell colistin without a prescription is operating outside Canadian law.

Is colistin covered by Canadian provincial health insurance?

Yes, colistin is covered by provincial health plans (like OHIP in Ontario) when prescribed by a hospital physician for approved indications. However, coverage is contingent on meeting stewardship criteria—the infection must be multidrug-resistant and colistin must be the appropriate choice.

What happens if I develop kidney problems while taking colistin?

Your doctor will monitor kidney function closely with blood tests. If kidney injury occurs, your dose may be reduced or the medication stopped if possible. Kidney injury from colistin is often reversible, but this is why regular monitoring is essential.

Are there safer alternatives to colistin approved in Canada?

Yes, for many infections. Colistin is only used when bacteria are resistant to all safer options. If safer antibiotics work against your infection, your doctor will use those instead. Colistin is truly a last resort.

Has Health Canada ever restricted or recalled colistin?

Health Canada has not withdrawn colistin approval, but it has updated prescribing guidance to reflect increased resistance concerns and the risks of nephrotoxicity. The drug remains approved and available, but use is appropriately restricted to serious, resistant infections.

Colistin Legal Status in Canada: Approved but Restricted

Colistin is legal in Canada and approved by Health Canada, but it's one of the most tightly controlled antibiotics in the country. Unlike over-the-counter painkillers, colistin can only be prescribed by physicians in hospital settings for severe, multidrug-resistant bacterial infections where all other antibiotics have failed. It has been approved since the 1950s, but its use remained rare until the 2000s, when resistant infections surged. Today, colistin is classified as a "last-resort" antibiotic in Canadian healthcare, meaning doctors use it only when the stakes are highest and no alternatives exist.

Colistin's Legal Status in Canada

Colistin holds Health Canada approval as a prescription medication. This means it has been assessed for safety and efficacy by Health Canada's Therapeutic Products Directorate (TPD) and is legally marketed in Canada. However, approval does not equal easy access. Colistin is a controlled pharmaceutical—not in the sense of a narcotic, but in the sense that its use is monitored and restricted to specific clinical circumstances.

What "Approved" Means in Canada

When Health Canada approves a drug, the manufacturer must demonstrate that:

The drug's benefits outweigh its risks
Manufacturing meets quality standards
The labelling accurately describes indications, dosing, and adverse effects
Clinical data supports the claims

Colistin cleared these hurdles and is listed in the Health Canada Drug Product Database, making it legally available for prescription. However, approval came decades ago (the original formulation in 1959), before modern randomized controlled trial standards were routine. Much of colistin's evidence base comes from observational studies in critically ill patients, not placebo-controlled trials.

Regulatory History: From Abandoned to Essential

The 1950s–1990s: First Approval, Then Abandonment

Colistin was first synthesized in 1949 and approved for clinical use in 1959. It was initially used broadly for infections, but fell out of favour by the 1970s–1980s because of a serious safety problem: kidney injury occurred in 30–60% of patients receiving intravenous colistin. As newer, less toxic antibiotics became available, colistin was shelved.

During this period, it remained legally approved in Canada but was rarely prescribed outside niche contexts (e.g., topical use for wound infections).

The 2000s: Regulatory Re-emergence

In the early 2000s, a global crisis unfolded: bacteria began developing resistance to nearly all standard antibiotics. Infections caused by Pseudomonas aeruginosa, Acinetobacter baumannii, and other multidrug-resistant organisms became untreatable with conventional drugs. Clinicians had no choice but to resurrect colistin.

Health Canada did not need to re-approve colistin—it was already approved. Instead, regulatory agencies worldwide (including Health Canada) updated clinical guidance to reflect its renewed role. The FDA, EMA, and Health Canada all issued or updated prescribing information to clarify that colistin should be used only when no other options remain.

Current Regulatory Framework in Canada

Prescription Requirements

Colistin is a prescription-only medication in Canada. It cannot be obtained without a doctor's order and is typically administered only in hospital settings by trained healthcare professionals. Retail pharmacies do not dispense colistin for home use—it is a hospital-based drug.

Indications Recognized by Health Canada

According to the Health Canada Drug Product Database and product monographs, colistin is indicated for infections caused by susceptible gram-negative bacteria, particularly those resistant to other antibiotics. Common clinical scenarios include:

Infections caused by Pseudomonas aeruginosa (resistant strains)
Acinetobacter baumannii infections
Other multidrug-resistant gram-negative pathogens

Health Canada's guidance emphasizes that colistin should be reserved for serious infections where susceptibility testing has ruled out all preferred alternatives.

Stewardship and Monitoring

Canadian hospitals operate antibiotic stewardship programs that govern which antibiotics can be prescribed and by whom. Colistin typically requires:

Approval from the hospital's infectious diseases physician or antimicrobial stewardship team
Evidence that the infection is resistant to standard antibiotics
Baseline kidney function tests (because colistin is nephrotoxic)
Regular monitoring of kidney function and drug levels during treatment

These safeguards are not enforced by a single federal agency but are standard practice in accredited hospitals across Canada.

Why Colistin Use Is Restricted: The Safety Picture

Kidney Toxicity

The primary reason colistin access is tightly controlled is nephrotoxicity. Clinical data shows that 30–60% of patients receiving intravenous colistin experience acute kidney injury (AKI). This is dose-dependent and often reversible, but in some cases it progresses to chronic kidney dysfunction.

Health Canada's approved product monographs include warnings about this risk and recommend:

Baseline creatinine clearance assessment
Dose adjustment for patients with renal impairment
Monitoring of serum creatinine and urine output during treatment

Neurotoxicity

Colistin can also cause neurological side effects, including tingling, numbness, and in rare cases, muscle weakness. These risks are documented in Health Canada–approved labelling.

Resistance Concerns

In 2015, researchers identified a transferable resistance gene (mcr-1) that allows bacteria to resist colistin. Health Canada, along with the WHO, the CDC, and other regulators, flagged this as a public health emergency. The existence of mcr-1 means colistin's status as a "last resort" is threatened. If resistance becomes widespread, there may be no reliable antibiotics left for multidrug-resistant infections.

This public health threat has reinforced the principle that colistin use must be minimized to preserve its effectiveness—another reason Canadian hospitals restrict its prescription to genuine last-resort scenarios.

Enforcement and Compliance

Health Canada's Role

Health Canada's Therapeutic Products Directorate (TPD) and the Biologic and Radiopharmaceutical Drugs Directorate (BRDD) monitor the safety and efficacy of approved drugs, including colistin. If safety concerns emerge post-market, Health Canada has the authority to:

Require label updates
Restrict indications
Issue safety communications
In extreme cases, withdraw approval

Since 2000, Health Canada has issued periodic Dear Healthcare Provider letters about high-risk antibiotics, but colistin-specific safety alerts have been limited. The main enforcement mechanism is hospital stewardship programs, which are overseen by provincial health authorities and accreditation bodies like Accreditation Canada.

Pharmacy Enforcement

Pharmacists in Canada check all prescriptions against Health Canada's approved indications and patient-specific factors (age, kidney function, drug interactions). A colistin prescription that does not align with approved use would be flagged and referred back to the prescriber.

What Consumers and Patients Should Know

You Cannot Buy Colistin Over the Counter

Colistin is not available for self-purchase in Canada. It is a prescription-only medication, typically given only in hospitals.

It Will Only Be Prescribed If You Have a Serious, Resistant Infection

If your doctor recommends colistin, it means antibiotics that are safer and more commonly used have not worked or are not suitable for your specific infection. This is not a casual decision.

Kidney and Neurological Side Effects Are Real

Colistin can damage your kidneys and affect your nervous system. If you receive colistin, you will need regular blood tests and clinical monitoring. Do not ignore symptoms like decreased urine output, tingling, or numbness—report them immediately.

Colistin Is Not Available for Non-Medical Use

There is no grey-market or unregulated colistin supply in Canada. The only legal source is a prescription from a licensed physician in a licensed hospital.

Clinical Research and Future Developments

Colistin is the subject of ongoing clinical research in Canada and globally. As of the latest data, 119 clinical trials involving colistin are registered internationally, many investigating:

Whether combination therapy (colistin + another antibiotic) is superior to colistin alone
Next-generation polymyxin antibiotics with lower toxicity
Optimal dosing strategies to maximize efficacy while minimizing kidney injury

Health Canada reviews data from these trials and updates guidance accordingly. Currently, no next-generation polymyxin has yet been approved in Canada, though the EMA and FDA have authorized some investigational variants for compassionate use in serious infections.

Key Takeaway

Colistin is legally approved and available in Canada, but access is highly restricted by design. Health Canada recognizes its value as a last-resort antibiotic, but also understands the serious risks. If you are prescribed colistin, it reflects a critical clinical need. Follow your doctor's instructions closely, attend all monitoring appointments, and report any adverse effects immediately.

Related Compounds

Other antibiotics with complex regulatory histories in Canada include polymyxin B, tobramycin, and tigecycline, which are sometimes used in similar resistance scenarios.

Learn more about key terms: multidrug-resistant bacteria and antibiotic stewardship.

Is Colistin Legal in Canada? Here's What You Need to Know