Humulin N Cartridge 100u/mL Suspension
Humulin N Cartridge
Insulin Isophane (Nph)
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Product of Canada.

Express Ships from Canada.

Prescription Required.
Product of Canada.
Express Ships from Canada.

Humulin N Cartridge contains insulin isophane, also known as NPH insulin, a type of intermediate-acting insulin. It is used to control high blood sugar in people with diabetes. This insulin product helps lower levels of glucose in the blood, thereby reducing the risks associated with high blood sugar, such as nerve problems, loss of limbs, and kidney damage.

How it’s Used


Humulin N should be injected under the skin as directed by your doctor, usually once or twice a day. The dosage is based on your medical condition and response to treatment. Do not inject into a vein or muscle because it won’t work as well.


Store unopened insulin isophane in the refrigerator. Do not freeze. Keep away from direct heat and light. Once opened, the product may be stored at room temperature or in the refrigerator. Check the product package for the exact storage temperature range.

Side Effects

The use of Humulin N Cartridge, like any medication, can lead to side effects, although not everyone experiences them. It’s important to be aware of these potential reactions to manage them effectively if they occur.

Common Side Effects

The most frequently observed side effects include:

  • Injection site reactions such as redness, pain, itching, hives, swelling, or inflammation. These usually resolve within a few days to a few weeks.
  • Hypoglycemia (low blood sugar levels), characterized by symptoms like dizziness, shaking, sweating, hunger, fast heartbeat, confusion, or feeling jittery.
  • Weight gain can occur as insulin therapy stabilizes your blood sugar levels.
  • Mild swelling in the arms or legs due to fluid retention.
  • Skin changes at the injection site (lipodystrophy), such as thickened or pitted skin.

Serious Side Effects

While less common, some serious side effects may require immediate medical attention:

  • Severe hypoglycemia, which can cause unconsciousness, seizures, or death if untreated.
  • Allergic reactions, including anaphylaxis, a severe, whole-body reaction that can be life-threatening. Symptoms include difficulty breathing, rapid heartbeat, swelling of the face, lips, or tongue, and severe rash or itching.
  • Hypokalemia (low potassium levels in the blood), leading to muscle cramps, weakness, irregular heart rhythms, or paralysis.
  • Vision changes, such as blurred vision, which can occur when first starting insulin therapy and should be monitored.
  • Swelling and heart failure in some people, particularly those with pre-existing heart conditions or those taking certain medications like thiazolidinediones (TZDs).

Managing Side Effects

  • Regularly monitor your blood sugar levels to detect hypoglycemia early.
  • Always carry a quick source of sugar (like glucose tablets) to treat low blood sugar episodes.
  • Rotate injection sites to prevent skin changes.
  • Stay hydrated and maintain a balanced diet to manage weight gain and fluid retention.
  • Consult your healthcare provider immediately if you experience severe side effects or allergic reactions.

Warnings and Precautions

When using Humulin N Cartridge, it’s important to be aware of certain warnings and precautions to ensure safe and effective use of the medication:

Hypoglycemia Risk

The most common risk associated with insulin, including Humulin N, is hypoglycemia, or low blood sugar. Be vigilant about monitoring blood sugar levels, especially when starting treatment, changing doses, or altering diet and exercise routines. Know the symptoms of hypoglycemia and how to treat them.

Hyperglycemia and Diabetic Ketoacidosis (DKA)

If you miss doses or do not take enough insulin, you may experience hyperglycemia (high blood sugar) or DKA, a serious condition that can lead to diabetic coma or death. Symptoms include excessive thirst, frequent urination, nausea, vomiting, drowsiness, dry skin, and a fruity breath odor.

Dosage Adjustments

Dosage may need adjustment in response to changes in physical activity, diet, illness, stress, or due to other medications. Always consult your healthcare provider before making any changes to your insulin regimen.

Allergic Reactions

Though rare, severe, life-threatening, generalized allergy, including anaphylaxis, can occur with insulin products, including Humulin N. Be aware of the signs of a serious allergic reaction and seek immediate medical help if they occur.

Heart Failure

Patients with heart failure should be monitored closely. Using insulin with thiazolidinediones (TZDs) can increase the risk of heart failure. If you are taking TZDs, inform your healthcare provider immediately if you experience any signs of heart failure such as shortness of breath, rapid weight gain, or swelling.

Kidney or Liver Impairment

Patients with kidney or liver impairment may require lower doses of insulin, including Humulin N, due to reduced insulin metabolism. Regular monitoring is essential.

Injection Site Rotation

Rotate injection sites within the same region to reduce the risk of lipodystrophy (abnormal tissue growth) and cutaneous amyloidosis (skin thickening).

Pregnancy and Breastfeeding

Consult your healthcare provider if you are pregnant, planning to become pregnant, or breastfeeding. Insulin needs may change during pregnancy and breastfeeding.

Children and Adolescents

The safety and effectiveness of Humulin N in children and adolescents should be assessed by a healthcare professional. Dose adjustments may be more frequent due to growth and hormonal changes.

Avoid Medication Errors

Always check the insulin label before each injection to avoid medication errors between Humulin N and other insulins.

Travel and Storage

When traveling, keep your insulin with you at all times. Do not store insulin in extreme temperatures as it may become ineffective.

Alcohol Consumption

Be cautious with alcohol consumption, as it can interfere with blood sugar control. Alcohol may increase the risk of hypoglycemia.


Illness, especially with nausea and vomiting, can affect insulin needs. Consult your healthcare provider on how to manage your insulin during illness.

Emergency Situations

Always wear a diabetic identification bracelet and carry emergency contact information. In case of a severe hypoglycemic event or diabetic ketoacidosis, immediate medical attention is necessary.

Drug Interactions

When using Humulin N Cartridge, it’s important to be aware of potential drug interactions that can affect blood glucose levels or the action of insulin. Here are some common drug interactions to consider:

Hypoglycemic Agents

Other diabetes medications, especially sulfonylureas and meglitinides, can increase the risk of hypoglycemia when used with Humulin N. Monitor blood glucose levels closely when starting or adjusting these medications.

Hyperglycemic Agents

Some drugs, like corticosteroids, thyroid hormones, and certain diuretics, can raise blood sugar levels, potentially requiring an adjustment in insulin dosage.


These medications, used for high blood pressure and heart conditions, can mask the symptoms of hypoglycemia, making it harder to recognize low blood sugar levels. They can also potentially affect insulin action.


Alcohol can both potentiate and delay the effects of insulin, leading to unpredictable changes in blood sugar levels. It’s important to monitor blood glucose more frequently when consuming alcohol.

Angiotensin-Converting Enzyme (ACE) Inhibitors

These can increase the hypoglycemic effect of insulin and may require a dosage adjustment.

Oral Contraceptives

Estrogen and progestogen in oral contraceptives can affect blood sugar control. Women taking these medications may need to adjust their insulin dosage.

Thiazolidinediones (TZDs)

When used with insulin, TZDs can increase the risk of heart failure and edema. Monitor for symptoms of heart failure, especially if you have a history of heart disease.

Monoamine Oxidase Inhibitors (MAOIs)

These can enhance the blood-glucose-lowering effect of insulin, increasing the risk of hypoglycemia.

Aspirin and Other Salicylates

These may increase the hypoglycemic effect of insulin, necessitating closer blood glucose monitoring.

Certain Antidepressants (SSRIs, SNRIs)

These medications can affect blood sugar levels, either increasing or decreasing them, and may require insulin dosage adjustments.

Antipsychotic Medications

Some antipsychotics, especially atypical antipsychotics, can increase blood sugar levels, potentially requiring a higher dose of insulin.

Herbal Supplements

Certain herbal supplements, like fenugreek, ginseng, and garlic, can affect blood sugar levels. Discuss with your healthcare provider before using these supplements.


This can increase blood sugar levels, which may necessitate a change in insulin dosage.


This can cause hypoglycemia, which may sometimes be followed by hyperglycemia.

Sympathomimetic Drugs

Drugs like epinephrine, albuterol, and terbutaline can increase blood sugar levels.


Particularly thiazide and loop diuretics, can affect blood sugar control.