Levothyroxine oral/injection and Phenytoin Extended-Release Capsules
Determining the interaction of Levothyroxine oral/injection and Phenytoin Extended-Release Capsules and the possibility of their joint administration.
In the database of official manuals used in the service creation an interaction registered by statistical results of studies was found, which can either lead to negative consequences for the patient health or strengthen a mutual positive effect. A doctor should be consulted to address the issue of joint drug administration.
Consumer:Using phenytoin together with levothyroxine can decrease the effects of levothyroxine. This can cause fatigue, weight gain, constipation, and low blood pressure. Talk with your doctor before using phenytoin while you are using levothyroxine. You may need a dose adjustment and may need to check your thyroid levels more often. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.
Professional:MONITOR: Carbamazepine and phenytoin may decrease exogenous thyroid plasma concentrations resulting in elevated thyroid stimulating hormone (TSH) and possible exacerbation of hypothyroidism. The mechanism may be induction of hepatic CYP450 enzymes responsible for thyroxine (T4) and triiodothyronine (T3) metabolism. In addition, T3 and T4 may be displaced from thyroxine binding globulin by phenytoin. Clinical data are limited.
MANAGEMENT: Clinical monitoring of patient response, including laboratory serum TSH concentrations, is recommended. Adjustment of the thyroid replacement dosage may be indicated when initiating or discontinuing phenytoin or carbamazepine therapy.
- "Multum Information Services, Inc. Expert Review Panel"
- Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
Generic Name: levothyroxine
Brand name: Levoxyl, Synthroid, Tirosint, Unithroid, Euthyrox, Levothroid, Tirosint-Sol
Synonyms: Levothyroxine
Generic Name: phenytoin
Brand name: Dilantin, Phenytek, Dilantin Infatabs, Phenytoin Sodium, Prompt
Synonyms: Phenytoin
In the course of checking the drug compatibility and interactions, data from the following reference sources was used: Drugs.com, Rxlist.com, Webmd.com, Medscape.com.
- Levothyroxine oral/injection-Phenytoin Infatabs
- Levothyroxine oral/injection-Phenytoin injection
- Levothyroxine oral/injection-Phenytoin Intravenous
- Levothyroxine oral/injection-Phenytoin Oral Suspension
- Levothyroxine oral/injection-Phenytoin Sodium
- Levothyroxine oral/injection-Phenytoin Sodium, Prompt injection
- Phenytoin Extended-Release Capsules-Levothyroxine Sodium
- Phenytoin Extended-Release Capsules-Levothyroxine Tablets
- Phenytoin Extended-Release Capsules-Levoxyl
- Phenytoin Extended-Release Capsules-Levsin
- Phenytoin Extended-Release Capsules-Levsin (Hyoscyamine Injection)
- Phenytoin Extended-Release Capsules-Levsin (Hyoscyamine Tablets)