Low blood sugar: what to do now and when it is an emergency

According to the CDC, below 54 mg/dL low blood sugar is severe, and it can cause seizures, fainting or coma. Call 911 if the person:

• Is not alert or cannot be woken up
• Has a seizure
• Cannot swallow safely

Never give food or drink to an unconscious person. If they have prescribed glucagon, use it as directed: the CDC says it is the best way to treat very low blood sugar, and that emergency care should be sought afterwards. Once they are awake and can swallow, give fast-acting sugar and then something with carbs and protein.

According to the CDC and MedlinePlus, the most common signs are:

• Shaking and sweating
• Hunger
• A fast or pounding heartbeat
• Nervousness, anxiety or irritability
• Dizziness, headache or tiredness
• Blurry or double vision
• Tingling or numbness of the skin
• Confusion or trouble thinking; if it drops very low, seizures or fainting

According to MedlinePlus, low blood sugar mostly affects people with diabetes who use insulin or certain diabetes pills, such as sulfonylureas (glyburide, glipizide or glimepiride), repaglinide or nateglinide. Many other diabetes medicines don’t lower blood sugar on their own. The most common causes are:

• Taking more insulin or medicine than intended, or at the wrong time
• Skipping a meal, eating too little or waiting too long to eat after your medicine
• Exercising more than usual
• Drinking alcohol without eating

Puerto Rico has the highest rate of diagnosed adult diabetes of any U.S. state or territory: 14.4% in 2021, according to the CDC. For diabetes control, see type 2 diabetes; if your problem is the opposite, see high blood sugar.

It is less common. According to MedlinePlus, it can come from alcohol, some medicines that are not for diabetes, a severe infection, severe heart, kidney or liver failure, a lack of certain hormones, some weight-loss surgeries or, rarely, a tumor of the pancreas. If your blood sugar has dropped and you don’t have diabetes, you need a full in-person evaluation; the doctor guides you and refers you.

You see Dr. Diana Nieves Castro, a Puerto Rico-licensed general practice physician with several years of emergency-department experience, in English or Spanish. She reviews your glucose readings with you, when the lows happen, what you eat, how much you exercise and how you are taking your insulin or medicines.

If your sugar drops often, the key is reviewing your treatment: if appropriate, the doctor adjusts your dose or changes your medicine, and we send your prescription to your pharmacy. If you are already our patient, that review can be a US$49 follow-up visit; if you are a new patient, it is a US$79 online doctor visit. If needed, we give you a lab order, for example for hemoglobin A1c and kidney function. For a glucagon or medicine refill, see prescription refills, and for ongoing control, chronic care by telehealth.

If the patient is under 21, a parent or legal guardian stays on camera for the whole visit and shows ID.