The ingredient in Benadryl that causes drowsiness is diphenhydramine. Commonly used as an antihistamine to treat allergies, diphenhydramine is also used as a sleep aid. Diphenhydramine is also classified as a CNS depressant, sedative and antiemetic.Know More
Following oral administration, dependent on dosage, drowsiness and other common side effects normally last between 4 to 6 hours. The side effects of diphenhydramine, such as drowsiness, are worsened by the use of alcohol, sedatives and tranquilizers, as well as MAOIs, other CNS depressants and hypnotics. These effects are more pronounced in the elderly.
Some other notable side effects of diphenhydramine include agitation, confusion, fatigue, irritability, paresthesia, blurred vision and depression. In overdose, symptoms may include excitement, ataxia, tremor, sinus tachycardia, fever, hallucination, athetosis, convulsions, seizures, hypotension, deep coma, cardiorespiratory collapse and death.Learn more about Side Effects
Dogs and cats that take Cerenia, an anti-vomiting medication generally used for motion sickness, will typically experience some drowsiness or lethargy. Common side effects also include allergic reactions, such as hives or difficulty breathing, and drooling, according to 1-800-PetMeds.Full Answer >
There are many mild to severe side effects of Zyrtec that can include drowsiness, dry nose, dry mouth, difficulty sleeping, throat pain, irregular heart beat, bronchospasm, a heart pounding sensation, liver problems, seizures, diarrhea, blurred vision, severe water retention and painful urination, notes WebMD. Some patients may also develop hepatitis or incur an allergic reaction that is life threatening.Full Answer >
According to Drugs.com, drowsiness is a common side effect of Mucinex. The medication contains dextromethorpan, a chemical that is known to cause sleepiness, as explained by National Health Service UK. Drugs.com also explains that Mucinex may cause headaches, gastrointestinal issues and dizziness.Full Answer >
Reported side effects of using Formula 303 include drowsiness and gastric upsets, explains Westminster Accident and Injury Center. Formula 303 is made from a herb known as valerian; side effects of using the plant include insomnia, excitability and headaches, notes WebMD.Full Answer >