Federal officials are warning people against using Neptune’s Fix, an antidepressant that has been linked to seizures, loss of consciousness and death.

The Food and Drug Administration said Neptune’s Fix can interact with other medicines in a “life-threatening way,” and is urging retailers to remove the product from shelves. The products may also contain other harmful ingredients not listed on the label, the agency said in a statement.

Neptune’s Fix contains tianeptine — a potentially dangerous substance that is not FDA-approved for any medical use but is illegally sold with claims to improve brain function and treat anxiety, depression, pain, opioid use disorder and other conditions. Tianeptine has been dubbed “gas station heroin,” due to its abuse and withdrawal from closely resembling that of opioid toxicity, Axios reported.

Neptune’s Fix and other tianeptine products are sold online and at gas stations, vape and smoke shops and other locations.

Manufacturer Neptune Resources LLC has agreed to voluntarily recall all lots of the Neptune’s Fix Elixir, Neptune’s Fix Extra Strength Elixir and Neptune’s Fix Tablets and people who have the products are urged to throw them away.

Tianeptine has also caught the attention of lawmakers in Washington, D.C. where bipartisan legislation was introduced this week to add it to Schedule III of the Controlled Substance Act, making it illegal to sell without a prescription.