Julie is functionally identical to Plan B One-Step. Both contain the same active ingredient, levonorgestrel, at the same dose of 1.5 mg. They work the same way, carry the same side effects, and prevent pregnancy at the same rate. The main difference is price: Julie typically costs significantly less than Plan B, which can run $40 to $50 at most pharmacies.
Same Ingredient, Same Dose
Plan B One-Step is the original brand-name levonorgestrel emergency contraceptive. Julie is a generic equivalent containing the exact same 1.5 mg of levonorgestrel in a single tablet. There is no difference in formulation that would make one more effective than the other. This is the same relationship as buying store-brand ibuprofen versus Advil: the medication inside is identical.
How Both Pills Work
Levonorgestrel prevents pregnancy primarily by delaying or stopping ovulation. If your body hasn’t yet released an egg, the pill disrupts the hormonal signals that trigger that release, so there’s nothing for sperm to fertilize. The FDA has concluded that the drug acts on ovulation and does not affect implantation or an existing pregnancy.
The timing of your cycle matters. If you take either pill well before ovulation (several days out), it’s highly effective at suppressing the process. But research shows that when taken very close to ovulation, within a day or two, the pill is much less reliable at preventing egg release. In studies where women took levonorgestrel one to two days before expected ovulation, more than 85 to 90 percent still showed signs of normal ovulation. This doesn’t mean the pill failed entirely in those cases, but it does explain why effectiveness drops the longer you wait.
Effectiveness by Timing
Both Julie and Plan B are most effective when taken as soon as possible after unprotected sex. In clinical research, the pregnancy rate was about 0.8% when the pill was taken within 72 hours, translating to roughly 87 to 90% effectiveness compared to the expected pregnancy rate without any contraception. Between 72 and 120 hours (three to five days), the pregnancy rate rose to 1.8%, with effectiveness dropping to 72 to 87%. The pill still offers meaningful protection in that later window, but every hour counts.
Side Effects Are the Same
Because the active ingredient is identical, Julie and Plan B produce the same side effects. Most are mild and resolve within a day or two. Common ones include nausea, headaches, fatigue, breast tenderness, abdominal cramping, and changes to your next period. Your period may arrive earlier or later than expected, and you might notice light spotting before it starts.
User-reported data from Drugs.com gives a rough picture of how often Julie users experienced specific side effects: about 30% reported cramps, 23% nausea, 14% sore breasts, and 11% headaches. These numbers come from self-reports rather than controlled studies, but they align with what’s documented for levonorgestrel generally.
Weight and Effectiveness
There has been ongoing debate about whether levonorgestrel works as well in people with higher body weight. Some health organizations in the UK have suggested considering a double dose (3 mg) for women over 70 kg (about 154 lbs) or with a BMI above 26. The American Society for Emergency Contraception has suggested a double dose may help for those with a BMI over 30. However, a review of historical data found no clear loss of pregnancy prevention in higher-weight users taking the standard single dose, and concluded that double-dose recommendations may have been premature. If weight is a concern for you, a copper IUD inserted within five days of unprotected sex is the most effective emergency contraceptive regardless of body size.
Drug Interactions to Know About
Certain medications can reduce how well levonorgestrel works by speeding up how quickly your liver breaks it down. These include some seizure medications (like carbamazepine and phenytoin), the antibiotic rifampin, the antifungal griseofulvin, and the herbal supplement St. John’s wort. If you take any of these regularly, the standard 1.5 mg dose may not be sufficient. This applies equally to Julie and Plan B.
Price and Where to Buy
The biggest practical difference between the two is cost. Plan B One-Step generally retails for $40 to $50. Julie is priced lower, often around $13 to $15, making it one of the most affordable levonorgestrel options available. Both are sold over the counter with no age restriction and no prescription required.
Julie is stocked at over 4,500 Walmart locations, 5,600 CVS stores, and 1,500 Target stores. Plan B is available at most pharmacies and grocery stores nationwide. Both can also be ordered online. If your local store is out of one brand, any levonorgestrel 1.5 mg product on the shelf will work the same way.