Vitamin C Injection

• You want to know how vitamin C injection differs from vitamin C tablets
• You have kidney stones or gout and want to check whether it is safe for you
• You want to compare high-dose (Merit-C) with the standard dose

If you already get plenty of vitamin C from your diet, we first consider together whether an injection is really needed.

• 01

  Where you are now, and where we start

  The conditions attached to vitamin C injection’s approval, and kidney- and G6PD-related contraindications

• 02

  The change you want, the impression you keep

  We first look at whether there is a reason oral vitamin C is not enough. The label limits injection to cases where taking it by mouth is difficult.

• 03

  How it differs from similar options

  We check for conditions in which it must not be given, such as calcium oxalate kidney stones, gout or G6PD deficiency.

• 04

  Health information and recovery schedule

  If pigmentation is your concern, we look together at whether vitamin C injection fits its cause or whether another treatment should come first.

Ascorbic acid injection is approved on the premise that oral intake is difficult.

In the MFDS drug database (nedrug), the dosage section for ascorbic acid injection states that it is “normally given orally, with injection limited to acute cases or cases where oral administration is difficult”. The approved dose is 50–1,000mg per day. Among its indications, “melasma, freckles and post-inflammatory hyperpigmentation” applies only where vitamin C deficiency or a metabolic disorder is presumed to be involved.

How it works

• 01

  Ingredient

  The active ingredient is ascorbic acid (vitamin C). It goes by its ingredient name rather than a nickname.

• 02

  Approval conditions

  The indications are prefaced by the condition “in acute cases or when oral administration is difficult”.

• 03

  Approved dose

  50–1,000mg a day, given subcutaneously, intramuscularly or intravenously once to several times a day. The label states that more than 1g a day may increase the risk of diarrhea and kidney stones.

• 04

  Pigmentation wording

  “Melasma, freckles and post-inflammatory hyperpigmentation” applies only where vitamin C deficiency or a metabolic disorder is presumed to be involved.

1. 01

   Contraindication check

   We ask about calcium oxalate kidney stones, hyperoxaluria, gout, cystinuria, thalassemia and G6PD deficiency.

2. 02

   Choosing the dose

   We set the dose based on the approved range and your health. High doses are explained on a separate page.

3. 03

   Infusion and monitoring

   We watch for reactions such as flushing, headache or heartburn, and if the product contains sulfites, we also check for asthma.

What the procedure is like

• Most people can return to normal activities straight away.
• On the day of the infusion, drink plenty of water as usual.
• If you develop flank pain or blood in your urine, see a urologist.

Safety & considerations

Vitamin C injection’s pigmentation-related indication is limited to cases involving a deficiency or metabolic disorder. It is not an injection that promises whitening. Individual responses vary.

1. During infusion

   Common reactions

   The product information lists reactions such as nausea, flushing and headache.

2. On the day

   Digestive symptoms

   Vomiting, diarrhea, heartburn or abdominal cramps may occur.

3. Within a few days

   Urine and flank pain

   Flank pain or blood in your urine may be related to stones — please get checked.

We could not find any official Korean guideline on high-dose administration. Differences are described based on the approved product information only.

• Q. Are there cases where I should have vitamin C as an injection rather than by mouth?

  The label limits injection to “acute cases or cases where oral administration is difficult”. This means that if you can take it by mouth, that is the default. Whether you really need an injection is something we decide together at your consultation.

• Q. Will vitamin C injections fade my melasma?

  Its approved indications include “melasma, freckles and post-inflammatory hyperpigmentation”, but only where vitamin C deficiency or a metabolic disorder is presumed to be involved. That does not cover every case of melasma, so we first find out what is causing the pigmentation. A vitamin C injection does not promise whitening, and depending on the cause, another treatment may need to come first.

• Q. I’ve had kidney stones — can I still have a vitamin C injection?

  For people with calcium oxalate kidney stones, 1g or more per day is contraindicated in the label. Even below 1g, please tell us about any history of stones. The medical team will decide whether it can be given.

• Q. I take gout medication — does that matter?

  Ascorbic acid injection is contraindicated in people with gout according to the label. If you have been diagnosed with gout or take medication for it, please be sure to tell us. Cystinuria, hyperoxaluria and thalassemia are also contraindications in the same label, so let us know if any of these apply to you.

• Q. My face feels hot after a vitamin C injection — is that normal?

  Flushing is one of the adverse reactions listed in the label. It usually passes, but if you also feel short of breath or get hives, it may be a hypersensitivity reaction — let us know straight away. The label also lists reactions such as nausea and headache alongside flushing, so tell us about any discomfort during the infusion.