Hydrocortisone cream, ointment and lotion: uses, side effects and cautions

Hydrocortisone is a corticosteroid, a medicine based on a hormone the body makes. For the skin it comes as a cream, an ointment or a lotion, in a range of strengths. The NHS calls it a mild steroid, which is why most versions can be bought from shops and pharmacies without a prescription, although some strengths are prescription only. Brand names mentioned by the NHS include Derma Care and HC45.

It is used for eczema, psoriasis, contact dermatitis, and reactions to insect bites and stings. Some products combine hydrocortisone with an antifungal for nappy rash, thrush, ringworm and athlete's foot.

Steroid medicines reduce inflammation and swelling, so the redness, itch and puffiness of a flare ease. The treatment calms symptoms but does not remove the underlying tendency to eczema or psoriasis, which is why long-term skin care matters as well.

Because it is mild, hydrocortisone is often the first steroid people try. Stronger products such as clobetasol or betamethasone sit higher on the scale and carry more risk of side effects.

Most adults and children aged 10 and over can use hydrocortisone creams, ointments and lotions. Under 10, a doctor or pharmacist should advise first.

It is unsuitable for acne, rosacea, cold sores, inflamed skin around the mouth known as perioral dermatitis, bacterial skin infections and chickenpox or shingles.

• Do not put it on cuts or wounds.

• Do not use it on the face, penis or vulva without talking to a pharmacist or doctor first, as the skin there is thin and easily damaged.

• Do not cover the treated area with a dressing or plaster.

• Do not swallow it; seek medical help if someone does.

Hydrocortisone is applied once or twice a day in a thin layer. The amount is measured in fingertip units: the length of cream squeezed from the tip of an adult finger to the first crease. One unit treats an area about twice the size of your palm.

The practical steps are to wash your hands, squeeze out the amount you need, rub it gently in until it disappears, and wash your hands again unless the hands themselves are being treated. Do not use it for more than 7 days unless a pharmacist or doctor has said so. People on a prescribed long-term course should not stop suddenly, because a withdrawal reaction can follow.

Using a little too much now and then is not a worry, but regular overuse raises the chance of side effects. The treated skin, and clothing or bedding that has touched the product, can burn more easily, so keep away from naked flames and do not smoke.

Common effects are thinning of the skin where it is used, stretch marks, an itchy rash, lighter or darker patches of skin and small red lines of blood vessels showing through.

Rare serious effects include allergic reactions with a swollen throat or tongue and difficulty breathing, blurred vision, weight gain, a puffy face, muscle weakness, dizziness, changes in hair growth, and skin that flares with redness, burning, intense itching or peeling after stopping.

• Call 111 if you have a serious side effect while using it, or soon after stopping.

• Mention bothersome side effects that do not go away to a pharmacist or doctor.

• Report suspected side effects through the Yellow Card scheme.

Check with a pharmacist or doctor before using it in pregnancy. Most types can be used, though the smallest amount for the shortest time may be recommended. While breastfeeding it can usually be used after taking advice; if the cream goes on the chest, wash it off with warm water before feeding. Breastfed babies rarely have side effects from a parent's skin steroid.

The NHS says other medicines are unlikely to affect hydrocortisone cream, and you can eat and drink as normal while using it.

If a mild steroid is not enough, a prescriber may move up to a stronger one or add a different type of treatment. Redness on the face that might be rosacea or acne is a different matter, because the NHS lists both as conditions where hydrocortisone is unsuitable. If the skin has not settled after the permitted days, the next step is a conversation with a pharmacist or doctor rather than a longer course.