Pharmacy Diabetes

insulin-mixtard50/50

Name of Medicine
Insulin (rys)
Presentation
  • Mixtard 50/50: 1 mL suspension contains 100 IU soluble insulin. (rys)/isophane insulin (rys) in the ratio 50/50. The suspension is cloudy, white and aqueous.
  • Insulin (rys) is produced by recombinant DNA technology using Saccharomyces cerevisiae.
Key Practice Points
Therapeutic Indications:
  • The treatment of insulin-requiring diabetes.

https://www.pbs.gov.au/medicine/item/12255B-1426C-1763T-2062M

Dose:
  • Mixtard 50/50 insulin is usually given once or twice daily when a rapid initial effect together with a more prolonged effect is required.
  • An injection should be followed by a meal or snack containing carbohydrates within 30 minutes.
  • Mixtard 50/50 is not to be administered intravenously. Insulin suspensions are not to be used in insulin infusion pumps.
  • Preparations containing cloudy insulins should be gently agitated by rolling between the hands (10 mL vials only) or gently shaken (Penfill only) before use to ensure the insulin is uniformly distributed throughout the liquid and the injection should be given immediately thereafter.
  • Mixtard 50/50 is administered subcutaneously in the abdominal wall, the upper arm, or the thigh.
  • The duration of action of Mixtard 50/50 may vary according to the dose, injection site, blood flow, temperature, and level of physical activity.
  • Injection sites should be rotated within the same region to reduce the risk of lipodystrophy and cutaneous amyloidosis Note: Diabetes MedsCheck with referral to healthcare team for education on injection technique and managing hypoglycaemia.
  • Insulin needles and pen needles should only be used once and discarded in an appropriate sharps container Note: Diabetes MedsCheck with referral to healthcare team for education on injection technique and managing hypoglycaemia.
  • Use in renal impairment: Mixtard 50/50 can be used in renal impairment. As with all insulins, glucose monitoring should be intensified, and dosage adjustment should occur on an individual basis.
  • Use in liver impairment: Mixtard 50/50 can be used in hepatic impairment. As with all insulins, glucose monitoring should be intensified, and dosage adjustment should occur on an individual basis.
Elderly:
  • The safety and efficacy of Mixtard 50/50 has not been established in the elderly.
Contraindications:
  • Hypoglycaemia
  • Hypersensitivity to insulin or any of the excipients
  • Insulin suspensions should not be administered intravenously
  • Insulin suspensions are not suitable for the treatment of ketoacidosis coma.
Precautions:
  • Hyperglycaemia – Inadequate dosing or discontinuation of treatment, especially in type 1 diabetes, may lead to hyperglycaemia and ketoacidosis. The first symptoms of hyperglycaemia usually developed gradually, over a period of hours or days. They include nausea, vomiting, drowsiness, flushed dry skin, dry mouth, increased frequency of urination, thirst, and loss of appetite as well as acetone breath. Untreated hyperglycaemic events maybe life threatening. Note: Diabetes MedsCheck with referral to healthcare team for sick day management plan and education.
  • Hypoglycaemia: Hypoglycaemia is the most common adverse effect of insulins. As with all insulins, particular caution (including intensified blood glucose monitoring) should be exercised in individuals who are at greater risk of clinically significant sequelae from hypoglycaemic episodes. Note: Diabetes MedsCheck with counselling on side effect profile and that hypoglycaemia is part of the side effect profile. If happening regularly consider referral to see HCP for adjustment of dose. Referral to healthcare team for glucose monitoring and counselling for managing hypoglycaemia. Regular blood glucose monitoring is essential in individuals on intensive insulin therapy and when there is a change in insulin type or dose.
  • Travelling with insulin: Before travelling between different time zones, an individual should be advised to consult their doctor or CDE, since this may mean that extra education may be needed due to different time zones. Note: Diabetes MedsCheck with referral to healthcare team for guidance.
Adverse Effects:
  • Hypoglycaemia: Hypoglycaemia is the most common adverse effect of insulins. As with all insulins, particular caution (including intensified blood glucose monitoring) should be exercised in individuals who are at greater risk of clinically significant sequelae from hypoglycaemic episodes. These include (but are not restricted to) change in the injection area improved insulin sensitivity (e.g., by removal of stress factors, weight loss); unaccustomed, increased, or prolonged physical activity. intercurrent illness (e.g., vomiting, diarrhoea); inadequate food intake; missed meals; and alcohol consumption. Note: Diabetes MedsCheck with counselling on side effect profile and that hypoglycaemia is part of the side effect profile. If happening regularly consider referral to see HCP for adjustment of dose. Referral to healthcare team for glucose monitoring and counselling for managing hypoglycaemia. Regular blood glucose monitoring is essential in individuals on intensive insulin therapy and when there is a change in insulin type or dose.
  • Visual Impairment: A marked change in glycaemic management can cause temporary visual impairment, due to temporary alteration in the turgidity and refractive index of the lens. As with all insulin regimens, intensification of insulin therapy with abrupt improvement in glycaemic management maybe associated with temporary visual impairment or worsening of retinopathy. However, long-term improved glycaemic management decreases the risk of progression of retinopathy. Note: Diabetes MedsCheck with education and referral to healthcare team for annual cycle of care.
  • Injection site and allergic reactions. As with any insulin therapy, lipodystrophy may occur at the injection site and delay insulin absorption. Other injection site reactions with insulin therapy include redness, pain, itching, hives, swelling and inflammation. Note: Diabetes MedsCheck with education on side effect profile and referral to healthcare team to establish correct injection technique.
  • Immune system disorders. Immediate type allergic reactions to insulin are rare. Such reactions to insulin (including insulin glargine) or the excipients may, for example, be associated with generalised skin reactions, angioedema, bronchospasm, hypotension, and shock, and maybe life threatening. Note: Diabetes MedsCheck with counselling on side effect profile and referral to hospital if allergic reaction occurs.
Pharmacokinetic Properties-Summary
  • Mixtard 50/50 is an intermediate-acting insulin preparation. Its hypoglycaemic effect after subcutaneous administration begins after approximately 0.5 hour, is maximal between 4 and 8 hours and terminates after approximately 24 hours. Mixtard 50/50 is not exactly equivalent to its component insulins.

For more information on Mixtard 50/50, please see https://www.ebs.tga.gov.au/ebs/picmi/picmirepository.nsf/pdf?OpenAgent&id=CP-2011-PI-02733-3

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