Patient Suitability

Side Effects

The Intensive level of the OPTIFAST VLCD Program is accepted as being safe with only minor, transient side effects being observed.

These side effects are generally the result of the rapid weight loss and ketosis and may include;

• sensitivity to cold
• halitosis
• headache
• hair loss
• irritability
• postural hypotension
• fatigue
• muscle cramps
• menstrual disturbances
• constipation and/or diarrhoea

These side effects are generally insufficient in magnitude or duration to warrant cessation of the program.

As with any major dietary adjustment, the first few days on the Intensive level of the OPTIFAST VLCD Program can be difficult and are commonly known as the ‘3 day challenge’.

As the body transitions into ketosis, patients may experience some transient side effects in the first 3 days such as:

• fatigue
• hunger
• lack of concentration
• nausea
• headaches

Typically, only mild ketosis occurs during the Intensive level of the OPTIFAST VLCD Program and most symptoms pass by days 4-6. By this time, they will experience an increase in energy and reduction in appetite which, through the Intensive level, is likely to result in consistent and successful weight loss.