Insulin glargine
Insulin glargine is a long-acting basal insulin used in type 1 diabetes and in type 2 diabetes when longer background insulin is needed alongside meals or other tablets. Different brands and concentrations (U100 vs U300 products) exist — never switch without training.
This medicine is part of the Diabetes medicines category.
Generic name: insulin glargine
Quick answers
Short replies to searches people often run before speaking to a clinician. For the overview of what the medicine is used for, see the short summary under the page title above.
What is it for?
Insulin glargine is a long-acting basal insulin used in type 1 diabetes and in type 2 diabetes when longer background insulin is needed alongside meals or other tablets.
How long does it take to work?
Onset varies by condition and dose. Your GP or pharmacist can explain what to expect and when to review.
What are common side effects?
Hypoglycaemia, injection site lumps, or mild allergic redness can occur.
Can you take paracetamol or ibuprofen with it?
Ask your GP or pharmacist before taking Insulin glargine with paracetamol or ibuprofen. Many adults use paracetamol for short periods when appropriate; NSAIDs such as ibuprofen need extra checks with your other medicines and health conditions.
More about what Insulin glargine is used for
Insulin glargine is a long-acting basal insulin used in type 1 diabetes and in type 2 diabetes when longer background insulin is needed alongside meals or other tablets.
Different brands and concentrations (U100 vs U300 products) exist — never switch without training.
How does Insulin glargine work, and how long does it take to work?
It provides a slow, relatively steady insulin level over many hours to control fasting glucose and background needs.
It does not cover meal spikes alone — rapid insulin or other plans cover food unless on a specific regimen.
How and when should you take Insulin glargine?
Inject subcutaneously at the same time each day as prescribed (some products allow morning or evening). Rotate sites to reduce lipohypertrophy.
Check you have the correct pen device and needle type your pharmacist demonstrated.
What are the common side effects of Insulin glargine?
Hypoglycaemia, injection site lumps, or mild allergic redness can occur.
Weight gain is possible when starting insulin.
Serious side effects of Insulin glargine — when to get urgent help
Severe hypoglycaemia with confusion or seizures needs emergency glucose and medical help.
Generalised allergic reactions are rare but urgent.
What if you miss a dose of Insulin glargine?
Missed basal doses need structured advice — often take when remembered unless close to next dose, but protocols vary by product — call your diabetes team or 111 if unsure.
Who should not take Insulin glargine?
Hypoglycaemia episodes without ability to self-manage need urgent review of regimen. Some people reduce or stop basal insulin in acute illness per sick-day rules — follow written advice only.
Can you take paracetamol or ibuprofen with Insulin glargine? — other interactions
Other diabetes drugs, alcohol, ACE inhibitors, and some antibiotics can alter hypo risk — review regularly.
Insulin glargine in pregnancy and breastfeeding
Insulin is standard in pregnancy for diabetes — doses change frequently; specialist antenatal diabetes care applies.
Blood tests and monitoring on Insulin glargine
Home glucose or CGM, HbA1c, foot checks, and annual reviews are usual.
What might your GP prescribe instead of Insulin glargine?
Insulin detemir, insulin degludec, or NPH may be basal alternatives depending on cost, preference, and control.
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Frequently asked questions about Insulin glargine
People also ask — common Google searches
- What is Insulin glargine used for?
- Insulin glargine is a long-acting basal insulin used in type 1 diabetes and in type 2 diabetes when longer background insulin is needed alongside meals or other tablets. Different brands and concentrations (U100 vs U300 products) exist — never switch without training.
- How long does Insulin glargine take to work?
- Onset varies by condition and dose. Your GP or pharmacist can explain what to expect and when to review. Always follow your prescriber’s follow-up plan.
- Can you take Insulin glargine with paracetamol or ibuprofen?
- Ask your GP or pharmacist before taking Insulin glargine with Paracetamol or Ibuprofen. Many adults use paracetamol for short periods when appropriate; NSAIDs such as ibuprofen need extra checks with your other medicines and health conditions.
- What are the side effects of Insulin glargine?
- Hypoglycaemia, injection site lumps, or mild allergic redness can occur. Weight gain is possible when starting insulin. See the sections below for more detail, including serious side effects and when to seek urgent help.
- Can insulin glargine be taken in the morning?
- Many people use a consistent once-daily time; some products allow flexibility. Follow your prescriber’s chosen schedule and the leaflet for your brand.
- What if my pen looks cloudy?
- Basal glargine pens should look clear. If appearance changes, do not inject — take the pen to your pharmacy for advice.
Need personalised advice?
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Often used with
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