Treating a Low When You Take Insulin
Reviewed by CDE Mehandi Sharma · Updated
Low blood sugar is generally a reading below 70 mg/dL, and in Type 1 it is the emergency you will meet most often. The treatment is simple and worth knowing by heart.
The early signs are shakiness, sudden hunger, sweating, a fast heartbeat, dizziness, headache, tiredness or trouble seeing clearly. Many people describe feeling abruptly and strangely unwell.
The 15-15 rule
- Take 15 to 20 grams of fast-acting glucose or carbohydrate immediately.
- Wait 15 minutes.
- Check your blood sugar again.
- If it is still below 70 mg/dL, repeat.
Fifteen grams is about three or four glucose tablets, three teaspoons of sugar or glucose powder in water, or half a cup of regular fruit juice or a regular soft drink.
Do not reach for chocolate, biscuits or milk sweets. The fat in them slows absorption, which is the opposite of what you need.
Once recovered, if your next meal is more than an hour away, eat a small snack containing some protein so you do not drift low again.
Treat the low first and work out the cause afterwards. And do not skip your next insulin dose out of fear — that trades a low for ketones.