Sweating and diabetes: when sweat signals low blood sugar

Sudden sweating: check your sugar

The main cause of sudden sweating in people with diabetes is hypoglycaemia, blood sugar that is too low. The NHS usually defines it as below 4 mmol/L, and the US CDC as below 70 mg/dL (about 3.9 mmol/L). Diabetes medicines sometimes lower blood sugar more than needed: the NHS names taking too much insulin and missing meals among the common causes.

Sweating with a hypo rarely comes alone. Signs listed by the NHS and the CDC:

• sweating, often sudden and cold;
• shaking, a fast heartbeat;
• hunger, dizziness, weakness;
• tingling lips;
• irritability, confusion.

What to do straight away

If your meter reads below 4 mmol/L or the signs look like a hypo, the NHS advises eating or drinking something sugary and fast-acting straight away: a small glass of juice or a sugary fizzy drink, or a few glucose tablets. Check your sugar again after 10 to 15 minutes. If it is still below 4 mmol/L, repeat and check again after 10 minutes. Once it has come up, eat something more filling so it does not drop again.

Agree the exact plan, including what and how much to keep at hand, with your endocrinologist: it depends on your medicines.

A damp pillow in the morning

Hypos can happen during sleep too. The NHS lists low blood sugar among the causes of night sweats, and the International Hyperhidrosis Society (IHHS) lists diabetes and hypoglycaemia. The CDC warns that you may wake up when your sugar is low, but you should not rely on it.

If you have diabetes and often wake up drenched in sweat, tell your doctor. The NHS specifically advises seeing a doctor if you have had hypos at night. Other causes of night sweats are covered in “Night sweats: when they are normal and when to see a doctor”.

When the nerves are involved

Long-standing diabetes can damage the nerves that control the internal organs and the sweat glands. This is called autonomic neuropathy. The US National Institute of Diabetes (NIDDK) describes two of its signs related to sweat:

• heavy sweating at night or while eating;
• uneven sweating: some parts of the body sweat while others stay dry, or the sweat glands hardly work at all.

Why sweat may not appear at all

According to the NIDDK, the same neuropathy can cause hypoglycaemia unawareness: blood sugar falls, but the usual signs such as sweating, shaking and a pounding heart do not come. The CDC adds that this raises the risk of a severe low. So in diabetes, the absence of sweat does not prove your sugar is fine: rely on your meter, or on a continuous glucose monitor if your doctor has prescribed one.

When to get urgent help

Call an ambulance (103 or 112 in Kazakhstan) if a person with diabetes is unconscious, does not respond, has a seizure, or their sugar does not come up after taking sugar again. The NHS and the NIDDK note that with a severe hypo the person needs help from others and, if a doctor has prescribed it in advance, a glucagon injection. Do not try to give food or drink to someone who is unconscious.

Do not put off seeing a doctor if sweating has become more frequent, especially at night or while eating, if low sugar keeps coming back, or if you no longer feel it coming.

Bottom line: sugar first, antiperspirant second

Sudden sweating with diabetes is a reason to check your sugar, not to apply antiperspirant. An antiperspirant does not treat diabetes and should not mask an important signal from your body.

But many people with diabetes also sweat heavily when their sugar is normal, for example in the underarms or palms since their teens. That kind of local sweating is a job for an antiperspirant. Apply OKEY only to intact skin: with diabetes, the NHS advises seeing a doctor about blisters or cracked skin on the feet.

OKEY is a long-lasting, fragrance-free antiperspirant for women and men in a 35 ml roll-on bottle. It suits all areas prone to excessive sweating. According to the instructions, it is applied in the evening before bed in a thin layer to clean, completely dry and intact skin, and any residue is washed off in the morning. OKEY is available on Kaspi for 7990 ₸ with a 14-day bottle return. Regular customers can buy it on our website okeystaydry.com for 6990 ₸ with free delivery to a Flip pickup point, without a return option. The buy button is below.