Your pharmacist can provide more information about clonidine and chlorthalidone.

Prof. Gray says there are alternative non-anticholinergic drugs for doxepin and chlorpheniramine.

chlorpheniramine maleate - to eliminate the effects of histamine - an antipruritic and anti-inflammatory effect.

Common human antihistamines safe for dogs are clemastine fumarate, diphenhydramine, chlorpheniramine, and hydroxyzine.

Do not take chlorpheniramine, carbetapentane, ephedrine, and phenylephrine for longer than 7 days in a row.

Alcohol may increase drowsiness and dizziness while taking chlorpheniramine and phenylpropanolamine.

Drugs other than those listed here may also interact with chlorpheniramine and phenylpropanolamine.

Do not take chlorpheniramine and phenylpropanolamine for longer than 7 days in a row.

Chlorpheniramine – known as trade names Chlor-Trimton, Chlor-tripolon, Piriton and HISTA-12

But keep in mind that some medications, such as diphenhydramine or chlorpheniramine, can make you sleepy.

Dangerous sedation, dizziness, or drowsiness may occur if chlorpheniramine, carbetapentane, ephedrine, and phenylephrine is taken with any of these medications.

Acetaminophen is used on its own or in combination with pseudoephedrine, dextromethorphan, chlorpheniramine, diphenhydramine, doxylamine, codeine, hydrocodone, or oxycodone.

Some anticholinergic medicines are available over the counter, such as the antihistamine chlorpheniramine, which is used to treat allergies.

Whereas, certain nonprescription antihistamines (i.e., chlorpheniramine and Benadryl) have also been linked to developing dementia.

For instance, first-generation antihistamines (e.g. chlorpheniramine and diphenhydramine) are more likely to cause the following side effects: